A survey was conducted at local colleges around Madison where 692 students were surveyed, and 421 replied that they were over 6 feet tall showing a standard error of 0.0084 in the average height of a college student.
The standard error is given by the formula given below:
[tex]$$SE= {s}/{\sqrt{n}}$$[/tex]
Where s is the standard deviation,
n is the sample size.
Now let us find out the standard deviation by using the formula given below:
[tex]$$s=\sqrt{\frac{(421-271.17)^2+(271.17-270)^2}{692-1}}$$[/tex]
After calculating we get that the standard deviation s is equal to $0.2208$.
Now let us plug the value of the standard deviation s and sample size n into the formula for standard error:
[tex]$$SE={s}/{\sqrt{n}}$$[/tex]
On substituting the respective values, we get [tex]$$SE={0.2208}/{\sqrt{692}}$$[/tex]
On solving, we get that the standard error is equal to 0.0084
Therefore, the standard error is 0.0084.
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ercury's perihelion slowly precesses around the sun by a bit less than 2 degrees per century. this precession can be fully accounted for by newton's theory of gravity, although general relativity also gives the same answer. group of answer choices true false
The statement is true. Mercury's precession can be fully accounted for by both Newton's theory of gravity and general relativity.
Newton's law of universal gravitation states that any two bodies in the universe are attracted to each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. This force can explain why the perihelion of Mercury is slowly precessing around the sun. According to Einstein's general theory of relativity, gravity is caused by the curvature of space-time around a massive body, such as the sun. This curvature of space-time causes Mercury to precess around the sun.
Newton's theory of gravity and general relativity provide equivalent explanations for the precession of Mercury's perihelion, which is a phenomenon in celestial mechanics. The precession of Mercury's perihelion is the slow rotation of the planet's elliptical orbit around the Sun's perihelion (the point of closest approach).It is well-known that Mercury's perihelion rotates by 42.98 arcseconds per century, or 1.39 degrees per century. This is caused by the gravitational influence of other planets, such as Venus and Jupiter, which produce small changes in Mercury's orbit. However, when this is taken into account, a tiny residual effect remains that cannot be accounted for using Newton's theory of gravity. This additional precession, known as the anomalous precession, can only be explained by general relativity.
The statement "Mercury's perihelion slowly precesses around the sun by a bit less than 2 degrees per century. This precession can be fully accounted for by Newton's theory of gravity, although general relativity also gives the same answer." is true.
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a spacecraft is in a circular orbit of mars at an altitude of 200 km. calculate its speed and its perio
The speed of the spacecraft in a circular orbit around Mars at an altitude of 200 km is approximately 3,543.62 m/s, and the period of the orbit is approximately 6,867.97 seconds or 1.91 hours.
To calculate the speed of a spacecraft orbiting Mars in a circular orbit, use the formula: v = √(GM/R)
Where: v = speed of the spacecraft in meters per second
G = gravitational constant 6.674 × 10⁻¹¹ N m²/kg²
M = mass of Mars (6.39 × 10²³ kg)
R = radius of the orbit (200 km + the radius of Mars, 3,389 km)
Substituting in the values, we get:
v = √((6.674 × 10⁻¹¹ N m²/kg²) × (6.39 × 10²³ kg) / (3.5895 × 10⁶ m))
v ≈ 3,543.62 m/s
Therefore, the speed of the spacecraft in a circular orbit around Mars at an altitude of 200 km is approximately 3,543.62 m/s.
The formula to calculate the period of a circular orbit is T = 2πR/v
Where: T = period of the orbit in seconds
R = radius of the orbit in meters (200 km + 3389.5 km = 3589.5 km = 3.5895 × 10⁶ m)
v = speed of the spacecraft in meters per second
Plugging in the values, we get:
T = 2π(3.5895 × 10⁶ m) / (3,543.62 m/s)
T ≈ 6,867.97 seconds
The period of the orbit is approximately 6,867.97 seconds or 1.91 hours.
Therefore, the speed of the spacecraft in the circular orbit is 3,584 m/s and the period of the orbit is 6,867.97 seconds.
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In Fig. two tiny conducting balls of identical mass m and identical charge q hang from nonconducting threads of length L. Assume that θ is so small that than θ can be replaced by its approximate equal, sinθ. Show tthat x=(2πε0mgq2L)1/3 given the equilibrium separation x of the ball.
For the given question, the expression of the equilibrium separation x of the ball should be [tex](Q^2L/2\pi \epsilon_0mg)^{1/3}[/tex].
Determining the equilibrium separation x of the ball Two tiny conducting balls of identical mass m and identical charge q are hanging from non-conducting threads of length L.
Let the distance between the balls be x when they are in equilibrium.
The net force acting on each ball due to the electric field of the other ball is given by:
[tex]F = (1 / 4\pi\epsilon_0) q^2/ x^2[/tex]
The tension in the threads is given by:
[tex]T = mg/cos\theta[/tex]
The system will be in equilibrium when repulsive force due to like charges is equal to the tension component in the horizontal direction.
[tex]Tsin\theta = (1 / 4\pi\epsilon_0) q^2/ x^2[/tex]
For small angles, sinθ ≈ θ,
[tex]\theta=x/2L[/tex]
so replacing T and theta we get,
[tex]mgx/2L=(1 / 4\pi\epsilon_0) q^2/ x^2[/tex]
[tex]x=(Q^2L/2\pi \epsilon_0mg)^{1/3}[/tex]
Thus the equilibrium separation between two charged masses is [tex](Q^2L/2\pi \epsilon_0mg)^{1/3}[/tex].
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1. about a trillion comets are thought to be located far, far beyond pluto in the______.
2. the bright spherical part of a comet observed when it is close to the sun is the ______.
3. a comet's ____ stretches directly away from the sun.
4. a comet's____ is the frozen portion of a comet.
5. particles ejected from a comet can cause a(n) ______ on earth.
6. the ______ extends from about beyond the orbit of neptune to about twice the distance of neptune from the sun.
1. About a trillion comets are thought to be located far, far beyond Pluto in the Oort Cloud.
2. The bright spherical part of a comet observed when it is close to the sun is the coma.
3. A comet's tail stretches directly away from the sun.
4. A comet's nucleus is the frozen portion of a comet.
5. Particles ejected from a comet can cause a meteor shower on earth.
6. The Kuiper Belt extends from about beyond the orbit of Neptune to about twice the distance of Neptune from the sun.
A comet is a small, icy, dusty celestial body. When a comet is close to the sun, it may emit gas and dust into space, producing a visible coma and a tail. The nucleus is the frozen portion of a comet, whereas the coma is the bright spherical part of a comet observed when it is close to the sun. The tail of a comet extends directly away from the sun.
The Oort Cloud is the location of about a trillion comets, far beyond Pluto. The Kuiper Belt, on the other hand, extends from beyond the orbit of Neptune to about twice the distance of Neptune from the sun. Finally, particles ejected from a comet can cause a meteor shower on earth.
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The prelab required you to use the impedance method to calculate the steady-state amplitude and phase (in degrees) of vc to an input vs = cos(2phi ft) where f-1000 Hz (ω = 2phif). The results from the prelab are . Ao=_____Phase, φ =_____degrees
The steady-state amplitude Ao = 50.03 degrees and phase, φ = -88.7 degrees by using the impedance method.
The given equation for vs is:
vs = cos(2phi ft) ...[1]
where, f = 1000 Hz,
therefore ω = 2φf
ω= 2000π radians/s
Let's find the impedance of the circuit elements.
The impedance of the resistor is R.
The impedance of the capacitor is:
Zc = 1/(jωC)
The impedance of the inductor is:
ZL = jωL
As the capacitor and resistor are connected in series, their total impedance is:
ZC+R = R + 1/(jωC) ...[2]
Now, as the inductor is connected in parallel with the combination of R and C, the total impedance of the circuit is:
Ztotal = (ZC+R) || ZL...[3]
Ztotal = (R + 1/(jωC)) || jωL
Ztotal = 1/[(1/R) + j(1/ωC - ωL)]...[4]
Comparing the real and imaginary parts of the equation [4],
we get, 1/R = √{(1/ωC - ωL)^2} ...[5]and
1/ωC - ωL = 0
or
ωL = 1/ωC ...[6]
From equation [5],
we get, R = 1/√{(1/ωC - ωL)^2} ...[7]
The magnitude of the input voltage Vs is 1 volt.
The amplitude of the steady-state output voltage, Vc is given by:
Voc = Ao x 1VoltA0
Voc = R/ZtotalA0
Voc = R/1/[(1/R) + j(1/ωC - ωL)]A0
Voc = R(1/R) + jR(1/ωC - ωL)A0
Voc = 1 + jR(1/ωC - ωL) ...[8]
From equation [6],
we get: L = 1/(ωC)
L = 1/(2π x 1000)
L = 1.59 x 10-7 H
Substituting L in equation [6],
we get: ωL = ωC
ωL = 1/2π x 1000 x 1.59 x 10-7
ωL = 0.1Ω
From equation [7], we get: R = 1000 Ω
Substituting the value of R and ωL in equation [8],
we get: A0 = 1 + j1000(1/2π x 1000 x 1.59 x 10-7 - 0.1)
A0 = √{(1^2) + (-50.03)^2}
A0 = 50.03 degrees
Let φ be the phase of the output voltage with respect to the input voltage.
Therefore, we have: tanφ = -50.03φ = -88.7 degrees
Therefore, Ao = 50.03 degrees and φ = -88.7 degrees.
Answer: Ao = 50.03 degrees, φ = -88.7 degrees.
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a 135-kg k g astronaut (including space suit) acquires a speed of 2.70 m/s m / s by pushing off with her legs from a 1900-kg k g space capsule. use the reference frame in which the capsule is at rest before the push.
A) What is the velocity of the space capsule after the push in the reference frame? B)If the push lasts 0.660 s , what is the magnitude of the average force exerted by each on the other? C)What is the kinetic energy of the astronaut after the push in the reference frame? D)What is the kinetic energy of the capsule after the push in the reference frame? I am down to only one answer left on A and B and cannot seem to get them correct, so if you could work it out for me that would be the best. Thank you.
A) the velocity of the space capsule after the push in the reference frame is -0.191 m/s.
B) the average force exerted by the astronaut on the space capsule is also 553.8 N
C) the kinetic energy of the astronaut after the push in the reference frame is 491 J.
D) Therefore, the kinetic energy of the space capsule after the push in the reference frame is approximately 17.2 J.
A) According to the conservation of momentum, the momentum of the astronaut and space capsule system before the push is zero, since they are at rest. After the push, the total momentum of the system is still zero. Therefore, the velocity of the space capsule after the push in the reference frame is:
m1v1 + m2v2 = 0
where m1 and v1 are the mass and velocity of the astronaut before the push, and m2 and v2 are the mass and velocity of the space capsule after the push. Substituting the given values, we get:
(135 kg)(2.70 m/s) + (1900 kg)(v2) = 0
Solving for v2, we get:
v2 = -(135 kg)(2.70 m/s) / (1900 kg) = -0.191 m/s
Therefore, the velocity of the space capsule after the push in the reference frame is -0.191 m/s.
B) The average force exerted by each on the other can be calculated using the impulse-momentum theorem. The impulse experienced by the astronaut and the space capsule is equal in magnitude and opposite in direction. Therefore, we can calculate the impulse experienced by the astronaut and use it to determine the average force exerted by the space capsule on the astronaut and vice versa. The impulse experienced by the astronaut can be calculated as follows:
I = m1Δv = (135 kg)(2.70 m/s) = 364.5 Ns
where Δv is the change in velocity of the astronaut due to the push.
The duration of the push is 0.660 s. Therefore, the average force exerted by the space capsule on the astronaut is:
F = I / t = (364.5 Ns) / (0.660 s) ≈ 553.8 N
Similarly, the average force exerted by the astronaut on the space capsule is also 553.8 N.
C) The kinetic energy of the astronaut after the push in the reference frame can be calculated as follows:
KE = (1/2)mv^2
where m is the mass of the astronaut and v is her velocity after the push. Substituting the given values, we get:
KE = (1/2)(135 kg)(2.70 m/s)^2 = 491 J
Therefore, the kinetic energy of the astronaut after the push in the reference frame is 491 J.
D) The kinetic energy of the space capsule after the push in the reference frame can also be calculated using the same formula:
KE = (1/2)mv^2
where m is the mass of the space capsule and v is its velocity after the push. The velocity of the space capsule after the push is -0.191 m/s. Substituting the given values, we get:
KE = (1/2)(1900 kg)(-0.191 m/s)^2 ≈ 17.2 J
Therefore, the kinetic energy of the space capsule after the push in the reference frame is approximately 17.2 J.
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The electric potential at a distance d
from a certain point charge is V relative to infinity. What is the potential (relative to infinity) at half the distance for the same charge?
A. V/4
B. 2 V
C. V/2
D. 4 V
The electric potential from a certain point charge when the distance is halve for the same charge will be V/2. Thus, the correct option will be C.
According to the Coulomb's law, the electric field is the gradient of the electric potential. And, the electric potential V is given by:V = kQ/r, where Q is the charge, r is the distance between the charge and the point where the potential is being calculated, and k is Coulomb's constant. Here, the electric potential at a distance d from a certain point charge is V relative to infinity.
The electric potential (relative to infinity) at half the distance for the same charge is the distance r/2, so:
V' = kQ/r
2V' = kQ/(d/2)
V' = 2kQ/d
V' = V/2
Therefore, the electric potential at half the distance for the same charge is V/2.
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the iron core of a transformer becomes ________________ when the current flows through the primary coil.
The iron core of a transformer becomes magnetized when the current flows through the primary coil.
Electrical energy is transferred between the main and secondary coils of a transformer through a magnetic circuit that is created by the iron core. A magnetic field that is continuously changing is produced in the iron core when an alternating current is fed through the primary coil. Energy is transferred between the coils as a result of the magnetic field's induction of a matching current in the secondary coil. Because of its high permeability and sensitivity to magnetism, the iron core can magnetize. A greater induced current is produced in the secondary coil as a result of the first coil's magnetic field being amplified by the iron core's magnetization. The effective transmission of electrical energy in a transformer depends on the magnetic characteristics of the iron core.
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Given Newton’s First Law of Motion, what do we reasonably expect an object to do given the following scenarios?
Part (a) An object sits at rest with no unbalanced forces acting upon it. What do we expect this object to do?
The object will begin to move at a constant velocity.
The object will remain at rest.
None of these answers.
The object will begin to move with a changing velocity
An object at rest will remain at rest and an object in motion will remain in motion with a constant velocity unless acted upon by an unbalanced force.
Newton's First Law of Motion often referred to as the Law of Inertia, is a fundamental principle of physics that states the following:
An object at rest remains at rest, and an object in motion remains in motion with the same velocity (which means both magnitude and direction) unless acted upon by a net external force.
In this scenario, there are no unbalanced forces acting upon the object, so it will continue to remain at rest.
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Resistors to be used in a circuit have average resistance 200 ohms and standard deviation 10 ohms. Suppose 25 of these resistors are randomly selected to be used in a circuit.
a) What is the probability that the average resistance for the 25 resistors is between 199 and 202 ohms?
b) Find the probability that the total resistance does not exceed 5100 ohms.
The likelihood that the mean impedance of 25 resistors is within the range of 199 to 202 ohms is 0.842, as per the principle of probability.
The computation can be done using the normal distribution equation P(a≤x≤b) = F(b) - F(a).
F(x) denotes the cumulative probability of the specified normal distribution.
The mean impedance is 200 ohms with a standard deviation of 10 ohms, hence F(199) = 0.155 and F(202) = 0.997. Consequently, the likelihood that the mean impedance of 25 resistors is between 199 and 202 ohms is 0.997 - 0.155 = 0.842.
The probability that the total impedance will be below 5100 ohms is 0.999. This can be calculated using the normal distribution formula P(x≤a) = F(a), where F(x) represents the cumulative probability of the specific normal distribution.
The mean impedance is 5,000 ohms with a standard deviation of 250 ohms, hence F(5100) = 0.999. Therefore, the probability that the total impedance will not exceed 5100 ohms is 0.999.
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The speed of propagation of a sound wave in air at 27 degrees (Celsius) is about 350 m/s. Calculate, for comparison, v(rms) for nitrogen molecules at this temperature. The molar mass of nitrogen is 28.0 g/mol.
The RMS speed of Nitrogen Molecules at this temperature is approximately equal to [tex]16.6\ m/s[/tex].
RMS speed of Nitrogen Molecules at this temperature is given by the root-mean-square (RMS) speed equation: [tex]$v_{rms} = \sqrt{\frac{3kT}{m}}$[/tex]
where,[tex]$k$[/tex] is the Boltzmann's constant,[tex]$T$[/tex] is the absolute temperature, and$m$ is the mass of a single molecule.
To calculate the root-mean-square (RMS) speed of nitrogen molecules at this temperature, we have to use the above formula.
Given, Temperature [tex]($T$) = 27^\circ C = $300\ K$[/tex]
The molar mass of nitrogen is given as [tex]$28.0\ g/mol$[/tex],
therefore, the mass of one molecule will be:
Mass of one nitrogen molecule [tex]= \frac{28.0}{6.022 \times 10^{23}}[/tex]g/molecule = [tex]4.64 \times 10^{-23}\ g/molecule[/tex]
The Boltzmann's constant is given as[tex]k = $1.38 \times 10^{-23}\ J/K[/tex]
Using the above values in the RMS formula, we have:
[tex]$v_{rms} = \sqrt{\frac{3kT}{m}} = \sqrt{\frac{3(1.38 \times 10^{-23}\ J/K)(300\ K)}{4.64 \times 10^{-23}\ g/molecule}}$[/tex]
The above expression evaluates to[tex]$v_{rms} = 16.6\ m/s$[/tex]
Therefore, the RMS speed of Nitrogen Molecules is [tex]16.6\ m/s[/tex].
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determine whether each geologic feature is being caused by tensional, compressional, or shear stresses by analyzing the directions of the forces being applied.
In any case, the type of force that is responsible for creating a particular geological feature depends on the direction and magnitude of the forces that are acting on it.
Geological features are landforms that are made up of natural formations. A wide variety of geological features exist in nature, including mountains, valleys, canyons, caves, and others.
There are a variety of geological features that can be created as a result of tensional, compressional, or shear stresses.
Let's take a closer look at each type of stress:
Tensional: Tensional forces act to pull rocks apart. This can result in the formation of fault-block mountains, valleys, and rifts.
Compressional: Compressional forces act to push rocks together. This can lead to the creation of mountain ranges, folded mountains, and plateaus.
Shear Stresses: Shear stresses act to twist or bend rocks. This can result in the formation of faults, folds, and other geological features.
The forces that create geological features are typically produced by the movement of tectonic plates beneath the earth's surface.
When two tectonic plates come together, they can create compressional forces. When they move apart, they can create tensional forces.
When they slide past each other, they can create shear stresses. Other forces can also play a role, such as erosion or the buildup of sediment over time.
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In the context of research evidence from the study conducted by Williams and McCririe, which of the following operates when a person picks up information critical to catching an object
both central and peripheral vision
In the context of research evidence from the study conducted by Williams and McCririe, both central and peripheral vision operate when a person picks up information critical to catching an object.
What is vision?
Vision is the sense that allows us to recognize and understand the physical world around us. Our brains then receive this information and convert it into the pictures that we see with our eyes.
Vision is the term used to describe the ability to see things with our eyes, such as color, form, and movement.
In the context of research evidence from the study conducted by Williams and McCririe, both central and peripheral vision operate when a person picks up information critical to catching an object.
Their research found that peripheral vision was essential to athletes performing in certain sports such as cricket, soccer, and baseball.
Peripheral vision, as well as central vision, are critical components of efficient eye tracking and hand-eye coordination.
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During a baseball game, the sound of the bat hitting the ball can be heard in most parts of the stadium. That sound is weaker at greater distances. What is the cause of this phenomenon?(1 point)
The sound waves are spread out over a large area.
The sound waves are blocked by people in the stadium.
The sound waves can only travel through certain materials.
The sound waves slow down as they move away from the bat.
The cause of this phenomenon is that the sound waves spread out over a large area as they move away from the source (the bat hitting the ball). Therefore, the sound waves become weaker at greater distances from the source.
What is Sound Wave?
A sound wave is a type of pressure wave that propagates through a medium such as air, water, or solids. It is created by the vibration of an object, which causes the molecules in the surrounding medium to vibrate and transfer energy from one molecule to the next. This vibration produces alternating areas of high and low pressure, which travel through the medium as a wave. Sound waves are characterized by their frequency, wavelength, amplitude, and speed, and can be measured and analyzed using various scientific instruments and techniques. Sound waves are important in many areas of science, technology, and everyday life, including music, communication, medicine, and environmental monitoring.
When a bat hits a baseball, it creates a disturbance in the air that moves outwards in all directions, creating sound waves. These sound waves carry energy, which is transferred from the bat to the air molecules. As the sound waves move away from the source, they spread out over a larger area. This means that the same amount of energy is distributed over a larger area, resulting in a decrease in the sound wave's intensity or amplitude.
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if you are looking at a photo with a grayscale filter, what can you likely conclude about the light waves emitted from the filtered photo relative to the original color photo?
A grayscale filter will reduce the intensity of, and in some cases completely remove, all the colors in an image. This means that the visible light waves emitted from the photo with a grayscale filter are less intense than the light waves emitted from a photo without the filter.
What is grayscale filter?A grayscale image is one in which each pixel's value is a single sample carrying just information about the intensity of the light. Shades of grey make up only grayscale images, a type of black-and-white or grey monochrome. Black at the lowest intensity contrasts with white at the highest.
An picture with a defined grayscale color-space that maps the sample values to the achromatic channel of a standard color-space, which is based on the observed characteristics of human vision, is said to be colorimetric (or, more precisely, photometric).
There is no specific mapping from such a color image to a grayscale image if the original color image has no defined color-space or if the grayscale image is not meant to have the same human-perceived achromatic intensity as the color image.
Define pixel.The smallest addressable element in a raster image, or the smallest point in an all points addressable display device, is called a pixel or picture element. The smallest component in most digital display systems that can be changed by software are pixels.
Each pixel serves as a sample of the original image; as more samples are used, the original is often more faithfully reproduced. Every pixel has a different level of intensity. The three or four component intensities of a color, such as red, green, and blue, or cyan, magenta, yellow, and black, are often used in color imaging systems to depict a color.
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If you stand on one foot while holding your other leg up behind you, your muscles apply a force to hold your leg in this raised position. We can model this situation as in Figure 1). The leg pivots at the knee joint, and the force that holds the leg up is provided by a tendon attached to the lower leg as shown Assume that the lower leg and the foot have a combined mass of 3.6kg, and that the combined center of gravity is at the center of Figure he knot What is the magnitude of this force? The london provides you hold your leg in this position the upper legeerts a force Express your answer with the appropriate units the lower le TARO? Value Units Sube
To keep the leg in the raised position, the tendon should provide 160N force.
The rotating force or moment of a force around a particular axis or pivot point is measured by torque. The tendency of a force to cause an object to spin along an axis is described as a vector quantity, torque.
Given: combined mass of the lower leg and the foot, m = 3.6kg
position of the center of gravity, r1 = 25cm
r = 0.25m
distance between tendon and lower leg, r2 = 5cm = 0.05m
torque applied will be τ = 3.6 × 10 × 0.25
τ = 8 N-m
the force applied by tendon
F = τ/ r2
F = 8/ 0.05
F = 160N
Therefore, To keep the leg in the raised position, the tendon should provide 160N force.
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Zach, whose mass is 80 kg, is in an elevator descending at 10 m/s.The elevator takes 3.0s to brake to a stop at the first floor.a. What is Zach's apparent weight before the elevator startsbraking ?b. What is Zach's apparent wight while the elevator is braking?a precise and step by step solution will help me understandthe problem.. thank you..
Explanation:
Let's use Zach's weight F = ma
F = 80 (9.81) = 785 N
at constant speed descending a = 9.81 and Zach's weight is still 785 N
As the elevator is slowing to a stop, Zach's apparent weight will increase
a = change in velocity / change in time = 10 m/s / 3s = 3.33 m/s^2
Zach's APPARENT weight will be F = ma where a = 9.81 + 3.33 m/s^2
F = 80 ( 9.81+3.33) = 1051 N
Storm clouds build up large negative charges, as described in the chapter. The charges dwell in charge centers, regions of concentrated charge. Suppose a cloud has -25 C in a 1.0-km-diameter spherical charge center located 10 km above the ground, as sketched in (Figure 1) . The negative charge center attracts a similar amount of positive charge that is spread on the ground below the cloud.
The charge center and the ground function as a charged capacitor, with a potential difference of approximately 4.1×108 V . The large electric field between these two "electrodes" may ionize the air, leading to a conducting path between the cloud and the ground. Charges will flow along this conducting path, causing a discharge of the capacitor−a lightning strike.
What is the approximate magnitude of the electric field between the charge center and the ground??
What is the approximate capacitance of the charge center + ground system?
If 12.5 C of charge is transferred from the cloud to the ground in a lightning strike, what fraction of the stored energy is dissipated?
If the cloud transfers all of its charge to the ground via several rapid lightning flashes lasting a total of 1 s, what is the average power?
The electric field between the charge center and the ground can be calculated using the formula:
E = V/d
where E is the electric field, V is the potential difference, and d is the distance between the two electrodes. In this case, the potential difference is 4.1×10^8 V and the distance is 10 km (which we need to convert to meters):
d = 10 km = 10,000 m
So, the electric field is:
E = 4.1×10^8 V / 10,000 m = 4.1×10^4 V/m
The capacitance of the charge center + ground system can be calculated using the formula:
C = Q/V
where C is the capacitance, Q is the charge stored, and V is the potential difference. In this case, the charge stored is -25 C (since it's a negative charge) and the potential difference is 4.1×10^8 V:
C = -25 C / 4.1×10^8 V = -6.1×10^-8 F
Note that capacitance is always positive, but in this case, it came out negative because the charge is negative.
The energy stored in a capacitor is given by the formula:
U = 1/2 CV^2
where U is the energy stored, C is the capacitance, and V is the potential difference. In this case, the energy stored before the lightning strike is:
U = 1/2 (-6.1×10^-8 F) (4.1×10^8 V)^2 = 5.1×10^14 J
If 12.5 C of charge is transferred from the cloud to the ground in a lightning strike, the energy dissipated is:
U' = 1/2 (-6.1×10^-8 F) (4.1×10^8 V - 12.5 C/(-6.1×10^-8 F))^2 = 3.3×10^14 J
So, the fraction of the stored energy that is dissipated is:
(U - U') / U = (5.1×10^14 J - 3.3×10^14 J) / 5.1×10^14 J = 0.35 or 35%
The average power of the lightning flashes can be calculated using the formula:
P = U/t
where P is the power, U is the energy transferred, and t is the time taken. In this case, the energy transferred is 25 C × 4.1×10^8 V = 1.03×10^10 J (since the potential difference is the same as before the lightning strike), and the time taken is 1 s (since the flashes last a total of 1 s):
P = 1.03×10^10 J / 1 s = 1.03×10^10 W or 10.3 GW (since 1 GW = 10^9 W)
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A resistor of 4Ω is connected to a series combination of two batteries, 8 V and 4 V. Calculate:
a) The current I.
b) The potential difference Uba
c) The potential difference Uba', when switch S is open.
Answer:
Explanation:
o calculate the current I, we can use Ohm's Law which states that I = V/R, where V is the total voltage across the resistor and R is the resistance of the resistor.
a) The total voltage across the resistor can be found by adding the voltage of the two batteries in series, which gives a total voltage of 8V + 4V = 12V.
So, I = V/R = 12V/4Ω = 3A.
b) The potential difference Uba is simply the voltage difference between the two batteries in the series combination, which is 8V - 4V = 4V.
c) When switch S is open, the circuit is broken and the potential difference Uba' becomes equal to the voltage of the 8V battery. So, Uba' = 8V.
calculate the distance moved by a car accelerating from rest at a constant rate of 2m/s squared for 5 s
Answer:
D=5
Explanation:
D=1/2*b*h
D=1/2*2*5
D=5
A 4x 103 -watt motor applies a force of 8x10 2newtons to move a boat at constant speed. How far does the boat move in 16 seconds?
a. 3.2 m
b. 5.0 m
c. 50 m
d. 80 m
The boat moves a distance of 80 m in 16 seconds when a force of [tex]8 \times 10^2[/tex] newtons is applied by a [tex]4 \times 10^3[/tex] watt motor. The correct answer is option d.
Power is defined as the rate at which work is done, and can be calculated using the formula:
Power = Work / Time
where Work is the amount of work done and Time is the time taken to do the work.
In this case, the power of the motor is given as [tex]4\times10^3[/tex] watts, and the force applied by the motor to move the boat at constant speed is given as [tex]8\times10^2[/tex] newtons. The work done by the motor in 16 seconds can be calculated as:
[tex]Work = Power \times Time[/tex]
[tex]Work = 4\times10^3\ watts \times 16\ seconds[/tex]
[tex]Work = 6.4\times10^4 \ joules[/tex]
The distance moved by boat can be calculated using the formula:
[tex]Work = Force \times Distance[/tex]
[tex]Distance = Work / Force[/tex]
[tex]Distance = 6.4\times10^4 \ joules / 8\times10^2\ newtons[/tex]
Distance = 80 meters
Therefore, the boat moves a distance of 80 meters in 16 seconds, which is option (d).
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aball is thrown horizontally from the top of a building 120 m high. the ball strikes the ground at a point 75 m horizontally away from and below the point of release. what is the resultant speed of the ball just before it strikes the ground?
The resultant speed of the ball just before it strikes the ground can be calculated by using the equation of motion. The equation of motion for an object in free fall is: s = u + at
Where:
s is the distance travelled. u is the initial velocity.a is the acceleration (due to gravity). t is the time.In this case, the initial velocity (u) is 0 (since it is thrown horizontally). The acceleration (a) is 9.81 m/s2, and the distance travelled (s) is 195 m (the distance from the top of the building to the point of impact).
Plugging the values into the equation: 195 = 0 + 9.81t. Solving for t, we get t = 19.84 s.
The resultant speed (v) can be calculated by using the equation v = u + at. Since u is 0, the equation simplifies to v = 9.81t. Plugging in the value of t that we found earlier, we get v = 195.87 m/s, which is the resultant speed of the ball just before it strikes the ground.
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What gauge pressure must a pump produce to pump water from the bottom of Grand Canyon (elevation 730 m) to Indian Gardens (elevation 1370 m)? Express your results in pascals and in atmospheres.
The gauge pressure that a pump must produce to pump the water from the bottom of Grand Canyon to Indian Gardens is about 627080 pascals and 6.17 atm.
What is the gauge pressure?The difference in elevation of the two points = 1370 - 730 = 640m
Density of water, `ρ` = 1000 kg/m³
g = 9.8 m/s²
The gauge pressure must a pump produce to pump water from the bottom of Grand Canyon (elevation 730 m) to Indian Gardens (elevation 1370 m).
Formula used: `P = ρgh`
where, `P` is pressure, `ρ` is density of water, `g` is acceleration due to gravity, `h` is height difference between the two points.
The gauge pressure that must a pump produce to pump water from the bottom of Grand Canyon to Indian Gardens is 627080 Pa and 6.17 atm.
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The period of a satellite, the time it takes for a complete revolution, depends on the satellite's a. radial distance. b. mass. c. weight. d. all of these e. none of these
The period of a satellite, the time it takes for a complete revolution, depends on the satellite's radial distance. Hence, the correct option is a.
What is a satellite?A satellite is an object in space that revolves around a planet, a moon, or even another satellite. Satellites, particularly those in the field of technology, enable the gathering of information and communication of information between two locations on Earth. Satellites can also be used for weather forecasting and military surveillance.
A revolution is one complete orbit around a central body for a satellite. The amount of time it takes for a satellite to complete one revolution is known as the satellite's period. As a result, it is clear that the period of a satellite depends on its radial distance. The closer a satellite is to the planet, the shorter its period would be, while the farther away it is, the longer its period would be.
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Suppose you are constructing a 95% confidence interval for the mean of a single sample, whose population standard deviation is known to be σ = 5. You calculate the sample size with some specified width (error) E. (a) Reducing your confidence level to 80%, and reducing your original width (error) E by a third ( 1 3 ), how much bigger will the new sample size be compared to the first sample size above? (Hint: find the scaled size using algebra). b) Suppose instead that your increase the sample size by a factor of 10 and you allow the confidence level to be 85%, how will the width (error) have scaled in size compared to the original width (error) E?
The sample size with some specified width error by reducing the confidence level to 80% is 3 times the original sample size and the width error which have been scaled in size compared to the original width error is by a factor of 10.
What is the sample size?When reducing the confidence level to 80% and the original width (error) E by a third, the new sample size will be 3 times the original size. To calculate this, use the formula n = (zα/2 / E)² × σ2.
If the original confidence level was 95%, then the original zα/2 = 1.96. If the new confidence level is 80%, then the new zα/2 = 1.282.
The original error was E, and the new error is 1/3 E. By substituting these values into the formula, we get n = (1.282 / (1/3 E))² × σ2. This simplifies to n = 3 × (1.96 / E)² × σ2, which is 3 times the original sample size.
If the original confidence level was 95%, then the original zα/2 = 1.96.
If the new confidence level is 85%, then the new zα/2 = 1.44.
The original error was E, and the new error is 10E.
By substituting these values into the formula, we get n = (1.44 / (10E))² × σ2.
This simplifies to n = (1.96 / E)² × σ2, which is 10 times the original sample size.
Therefore, the width (error) will have scaled in size by a factor of 10 compared to the original width (error) E.
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A telephone pole casts a clear shadow in the light from a distant head lamp of a car, but no such effect is noticed for the sound from the car horn. why?
Answer:
A telephone pole casts a clear shadow in the light from a distant head lamp of a car, but no such effect is noticed for the sound from the car horn. Why? Answer: The sound and light both are waves. But the wavelength of sound waves is very large as compared to the wavelength of light waves.
Explanation:
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the volumetric flow rate of water flowing through a pipe is 5 l/s, and the density of water is 1 kg/l. what is the mass flow rate? multiple choice question. 0.05 kg/s 0.005 kg/s 5 kg/s 50 kg/s 0.5 kg/s
The volumetric flow rate of water flowing through a pipe is 5 l/s and the density of water is 1 kg/l. This means that the mass flow rate is 5 kg/s. The correct answer is 5 kg/s.
The mass of a liquid passing in one unit of time is known as the mass flow rate. In other terms, the mass flow rate is the rate at which liquids move across a given region. The mass flow is a direct function of the liquid's density, velocity, and cross-sectional area.
The formula to find the mass flow rate of a substance is given as:
mass flow rate = density × volumetric flow rate
The given volumetric flow rate of water = 5 L/s
The density of water = 1 kg/L
Thus, the mass flow rate of water = 1 × 5 = 5 kg/s
Therefore, the answer is 5 kg/s.
The mass flow rate of water when the volumetric flow rate of water flowing through a pipe is 5 L/s, and the density of water is 1 kg/L is 5 kg/s.
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Una tabla de madera mide 61. 6cm como se expresa en metros esa longitud
The length of the board of wood expressed in meters is 0.616 m.
To convert 61.6 cm to meters, we can use the formula:
Length in meters = Length in centimeters ÷ 100
Plugging in the given value, we get:
Length in meters = 61.6 cm ÷ 100 = 0.616 m
Wood is a natural composite material made of cellulose fibers, lignin, and hemicelluloses, which are held together by a complex network of bonds. The cellulose fibers provide strength and rigidity, while the lignin acts as a binder, holding the fibers together. The hemicelluloses are responsible for the elasticity and flexibility of the material.
Wood has many interesting physical properties that make it a valuable material in a wide range of applications. For example, it is a good insulator, making it useful for construction and electrical applications. It is also a good acoustic absorber, making it useful in musical instruments and recording studios.
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Complete Question:
A board of wood measures 61.6 cm as that length is expressed in meters
Two 4.4 kg bodies, A and B, collide. The velocities before the collision are A = (28i + 27j) m/s and B = (9.8i + 1.8j) m/s. After the collision, 'A = (3.7i + 3.2j) m/s. What are (a) the x-component and (b) the y-component of the final velocity of B? (c) What is the change in the total kinetic energy (including sign)?
Answer:jfnvufhdfiprhfpiurgh8rhvjm vjfnb
Explanation:
why is europa considered a good candidate for the possible existence of life?
Europa is considered a good candidate for the possible existence of life because it has a subsurface ocean of liquid water that is believed to be in contact with a rocky seafloor, which provides a source of chemical energy and nutrients that could support life.
Additionally, observations by the Galileo spacecraft and ground-based telescopes suggest the presence of plumes of water vapor and other materials erupting from Europa's surface, providing a possible means for organic molecules to reach the surface and potentially support life.
Furthermore, Europa is believed to have a relatively stable environment and is shielded from harmful solar and cosmic radiation by its thick ice crust, which could protect any potential life forms from harmful radiation.
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