Answer:
7 minutes
Explanation:
Explanation:
Power = work / time
Power = force × distance / time
500 W = 210 N × 1000 m / t
t = 420 s
t = 7 min
A negatively charged plastic comb is brought close to, but does not touch, a small piece of paper. If the comb and the paper are attracted to each other the charge on the paper
A) must be negative
B) may be positive or neutral
C) may be negative or neutral D)must be positive
If the comb and the paper are attracted to each other the charge on the paper, is D)must be positive
Laws of electrical attraction
This states that
Like charges attract Unlike charges repelNow, given that a negatively charged plastic comb is brought close to, but does not touch, a small piece of paper. If the comb and the paper are attracted to each other the charge on the paper, this implies that both the negatively charged plastic comb and the paper have opposite charges.
Since the charge on the plastic comb is negative, this means that the charge on the paper must be positive
So, if the comb and the paper are attracted to each other the charge on the paper, is D)must be positive
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How far back into the universe are we able to see? Explain.
Answer:
About 46 billion light years Because space expands so what we didn’t see before is what we could see now. An example could be how everyone thought Pluto was a regular sized planet but once you get a look at the bigger picture and compare it to other thing in space we now know Pluto is a dwarf planet.
What is the absolute error expression of this ?
Answer:
n=(A+B)+k4
Explanation:
because if u add all the things to it u will get that
The weight of your science book presses on the desk.
A. Gravity pulls on the book.
B. Gravity pulls on the desk.
C. The desk pushes on the book.
Answer:
A. Gravity pulls on the book :)
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How many times does the light beam shown in FIGURE 26-59 reflect from (a) the top and (b) the bottom mirror?
Answer:
5
Explanation:
PLEASE HELP!! A TOTAL OF 50 POINTS WHEN GIVEN BRAINLIEST!!
Part A: Find the work done in lifting 1 L of blood (mass 1 kg ) from the foot to the head of a 1.9 m -tall person.
Part B: If blood circulates through the body at the rate of 5.0 L/min , estimate the heart's power output. (Your answer underestimates the power by a factor of about 5 because it neglects fluid friction and other factors.)
Explanation:
for part A:
work done is equal to change in potential energy which is
MgH
so the answer is 1.9 × 1 × 9.81
ANSWER FOR PART A: 18.639
FOR PART B:
power = flow rate x gh
= 5×9.81×1.9
93.195 watts
A capacitor of cylindrical shape as shown in the red outline, few cm long carries a uniformly distributed charge of 7.2 uC per meter of length. By constructing a suitable Gaussian surface around the wire, Find the magnitude and direction of the electric field at points (a) 5.5 m and (b) 2.5 m perpendicular from the center of the wire. Show your detailed calculations and comment on the results.
Hi there!
Begin by using Gauss' Law to find the electric field.
[tex]\oint {E \cdot} \, dA = \frac{Q_{encl}}{\epsilon_0}[/tex]
E = Electric field (N/C)
dA = differential area element
Q = enclosed charge (C)
ε₀ = Permittivity of free space (8.85 * 10⁻¹² C²/Nm²)
We can construct a large cylinder around the wire in order to determine the electric flux. The electric field lines will pass through the LATERAL surface area of the cylinder, so:
[tex]A = 2\pi rL[/tex]
Where 'L' is the length of the cylinder and 'r' is the distance from the capacitor.
The enclosed charge is equivalent to the charge per meter length (λ) multiplied by the length, so:
[tex]\oint {E \cdot} \, dA = \frac{\lambda L}{\epsilon_0}[/tex]
We can rewrite the dot product as EA (where cosθ = 1 since the normal vector points in the direction of the field).
A = the lateral surface area of a cylinder, so:
[tex]E * 2\pi rL = \frac{\lambda L}{\epsilon_0}[/tex]
Rearrange to solve for 'E'.
[tex]E = \frac{\lambda L }{2\pi r L \epsilon _0}\\\\E = \frac{\lambda }{2\pi r \epsilon_0}[/tex]
a)
Plug in the distance into 'r'.
[tex]E = \frac{\lambda }{2\pi r \epsilon_0} \\\\E = \frac{0.0000072}{2\pi * 5.5 * (8.85 * 10^{-12})} = \boxed{23542.18 \frac{N}{C}}[/tex]
b)
Repeat:
[tex]E = \frac{\lambda }{2\pi r \epsilon_0}\\\\E = \frac{0.0000072}{2\pi * 2.5 * (8.85 * 10^{-12})} = \boxed{51792.8 \frac{N}{C}}[/tex]
We can see that the distance from the wire is INVERSELY related to the electric field strength by a power of r⁻¹. The field strength DECREASES as the distance INCREASES.
a diamond sparkles more than a glass cut to similar shapes,why?
Answer:
because when you shape glass it's not a shiny as diamond
Is this d or not? Pls helppppp
Answer:
B load
Explanation:
definitely not D.
a power source is a battery or a power generator (like at power plants or on good old-fashioned bicycles to have light in the dark).
the fan uses the electrical energy coming from a power source.
if it would be a "propeller" at a wind farm (where power is generated by the wind blowing in between the blades making them turn and as such generating electrical power), then yes, but that is not what the description is telling us.
so, since it is using electrical power to do something, it is a load on the net or circuit or grid.
because it takes out some energy, the actual power generator has to work a little bit harder to maintain the energy level in the grid. just like you have to work harder when you have to carry a bigger weight (or load). hence the name.
the fan will have some conducive material inside (an electrical motor is a structure of coils of wires around magnets, and the power goes through these wires, so they have to be conductive).
and the fan will have a switch, which breaks or establishes the flow of electric energy and therefore determines, if and when the fan is working or not.
she incorrect? Select all that apply.
because electromagnetic waves can only travel in gases
А
B
because electromagnetic waves can only travel through solids
С
because electromagnetic waves only come from the Sun
D
because electromagnetic waves are not created using force on a medium
m
because electromagnetic waves are created using accelerating charges
F
because electromagnetic waves require a medium to travel
electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.
hope it helps...!!!
A __________is a large cool star located in the top right of the HR diagram.
Answer:
Vermeer star is located at the top of large Venus
What is an analogy of two different roads or rivers to compare a series and parallel circuit?
Answer:
In a series circuit, the same amount of current flows through all the components placed in it. On the other hand, in parallel circuits, the components are placed in parallel with each other due to which the circuit splits the current flow.
any help here please ???
Answer:
16 reflection,incidence
Momentum questions help
Answer:
a=25000 kg•m/s
b=1200 kg•m/s
c=what force?
Explanation:
for question a you multiply the mass which is 1000kg with velocity 25m/s.
for question b you multiply the force 60n with time 20s
Aresultant vector is the *blank* of two or more vectors.
Answer:
Vector sum.
Adding two things together to make one is usually referred to as a sum, therefore, we can identify this as that.
Two particles are 15 meters apart.
Particle A has a charge of 6.0*10^-4 C
Particle B has a charge of 5.0*10^-4 C.
The resulting Coulomb force is 12 N. At the same distance, what combination of charges would yield the same Coulomb force?
A. Particle A: 8.0*10^-4 C, and Particle B: 3.0*10^-4 C
B. Particle A: 12.0*10^-4 C, and Particle B: 2.5*10^-4 C
C. Particle A: 9.0*10^-4 C, and Particle B: 8.0*10^-4 C
D. Particle A: 9.0*10^-4 C, and Particle B: 3.0*10^-4 C
Considering the Coulomb's Law, the combination of particle A: 12.0×10⁻⁴ C and particle B: 2.5×10⁻⁴ C would yield the same Coulomb force of 12 N.
Coulomb's LawCharged bodies experience a force of attraction or repulsion on approach.
From Coulomb's Law it is possible to predict what the electrostatic force of attraction or repulsion between two particles will be according to their electric charge and the distance between them.
From Coulomb's Law, the electric force with which two point charges at rest attract or repel each other is directly proportional to the product of the magnitude of both charges and inversely proportional to the square of the distance that separates them:
[tex]F=k\frac{Qq}{d^{2} }[/tex]
where:
F is the electrical force of attraction or repulsion. It is measured in Newtons (N).Q and q are the values of the two point charges. They are measured in Coulombs (C).d is the value of the distance that separates them. It is measured in meters (m).K is a constant of proportionality called the Coulomb's law constant. It depends on the medium in which the charges are located. Specifically for vacuum k is approximately 9×10⁹ [tex]\frac{Nm^{2} }{C^{2} }[/tex].The force is attractive if the charges are of opposite sign and repulsive if they are of the same sign.
This caseIn this case, you know that two particles are 15 meters apart and the resulting Coulomb force is 12 N.
On the other side, you know:
Particle A: 8.0×10⁻⁴ C, and Particle B: 3.0×10⁻⁴ CParticle A: 12.0×10⁻⁴ C, and Particle B: 2.5×10⁻⁴ CParticle A: 9.0×10⁻⁴ C, and Particle B: 8.0×10⁻⁴ CParticle A: 9.0×10⁻⁴ C, and Particle B: 3.0×10⁻⁴ CReplacing in the Coulomb's Law, you get:
[tex]F=9x10^{9} \frac{Nm^{2} }{C^{2} }\frac{(8x10^{-4}C) (3x10^{-4} C )}{(15 m)^{2} }[/tex] → F= 9.6 N[tex]F=9x10^{9} \frac{Nm^{2} }{C^{2} }\frac{(12x10^{-4}C) (2.5x10^{-4} C )}{(15 m)^{2} }[/tex] → F= 12 N[tex]F=9x10^{9} \frac{Nm^{2} }{C^{2} }\frac{(9x10^{-4}C) (8x10^{-4} C )}{(15 m)^{2} }[/tex] → F= 28.8 N[tex]F=9x10^{9} \frac{Nm^{2} }{C^{2} }\frac{(9x10^{-4}C) (3x10^{-4} C )}{(15 m)^{2} }[/tex] → F=10.8 NFinally, the combination of particle A: 12.0×10⁻⁴ C and particle B: 2.5×10⁻⁴ C would yield the same Coulomb force of 12 N.
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2. What value did you calculate for the index of refraction of the acrylic block in Part 2? How does your value compare to the accepted value of 1.50? Calculate the percentage error. Different materials have distinct indexes of refraction. Explain how you might identify a material based on experiments like this one. Mention at least one of the difficulties in identifying materials based on their indexes of refraction.
The percentage error in calculated value of the refractive index of acrylic block is calculated using the formula: (true value - calculated value/true value) × 100%.
What is refractive index of a refracting medium?The refractive index of a medium is the ratio of the sine of the angle of incidence on the medium and the sine of the angle of refraction.
Refractive index = sin i/sin rwhere;
i is the angle of incidencer is angle of refraction.The refractive index of a medium increases with density of the medium.
To determine the percentage error in determining the refractive index of a medium, the following formula is used:
Percent error = error/true value × 100%Therefore, the percentage error in calculated value of the refractive index of acrylic block is the ratio of the error and true value multiplied by 100%.
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The centripetal force is proportional to the _____. mass velocity squared inverse of the radius All of the above
Answer:
Velocity squared.
Explanation:
We know that,
[tex]\text{F}_{\text{Centripetal}} = \dfrac{mv^2}{r}, \text{which implies} ~\text{F}_{\text{Centripetal}} \propto v^2[/tex]
9. aDefine refraction of light. Draw the ray diagram when an object is placed at C in a concave mirror Write any two natures of that image
Answer:
the process of bending of light when travling throw different mediume is called refraction of light.
acar start from rest and go with velocity of 4m/s for 4second what is acceleration of car
Answer:
1 m/s^2
Explanation:
The formula for accleration is a=Δv/Δt
where, Δv = final velocity - initial velocity = 4 - 0 = 4
initial velocity = 0 since the car starts form rest and final velovity is 4 as the car goes from rest till 4 m/s
Δt = 4 since the car takes 4 seconds to reach a velocity of 4m/s
Hence, a = 4 m/s / 4 s = 1 m/s^2
Answer:
1m/s
Explanation:
Given
initial velocity(u)=0
final velocity(v)=4m/s
timetaken (t)=4
Aceleration(a)=v-u÷t
now
=4-0÷4
=1m/s
Suppose that a car speaker produces sound waves with a frequency of 4000 Hz. As the car speaker moves away from an observer, which of the
following occurs?
Frequency is reduced with the sound waves being less heard when the speaker moves away from an observer.
What is Frequency?
This is defined as the number of occurrences of a repeating event per unit of time.
As the speaker is moved away from the observer, the wavelength increases and the frequency decreases thereby resulting in less sound being heard.
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Two people of equal mass attempt a tug-of-war with a 10 m long rope
while standing on ice. On pulling the rope, they both slide towards
each other. What will be the acceleration for each person?
Answer:
Explanation:
As the poster has noted above in comment, the acceleration for each person will be the same. This is because when they tugon the rope, there will be tension force on the rope pulling the two persons towards each other. The tension force will be the same for them. As they also have equal mass, by Newton's Second Law of Motion, Force = mass * acceleration, their acceleration will be the same.
A light bulb operating at a dc voltage of 120 V has a power rating of 60 W. How much current is flowing through this bulb
[tex]\\ \rm\rightarrowtail I=\dfrac{P}{V}=\dfrac{60}{120}=\dfrac{1}{2}=0.5A[/tex]
A stage has a radius R = 2.00 m and a mass M = 100 kg. The stage, which has a circular disk
shape, rotates in a horizontal plane, without any friction, about a vertical axle. Sandra has a
mass of m = 60.0 kg and she walks from the rim of the stage toward the center. Calculate the
angular speed when she reaches a point r = 0.500 m from the center, if the angular speed of the
system is 2.0 rad/s when Sandra is at the rim
i want the answer of this exercise
A ballplayer catches the ball 4 seconds after throwing it straight up in the air. What speed did he throw it and how high did it go?
Answer:
Speed of the ball when it was thrown = 16.67 m/s
Height reached by the ball = 14.16 s
Explanation:
Given time in the ball comes to the same height from where the ball was thrown is 3.4 s.
Let us assume that the ball was thrown with a speed of u in the upward direction. Since only gravitational force acts on the particle in the downward direction, it has a constant acceleration in the downward direction.
We also know that a particle has the same magnitude of velocity when it is under a free fall at a fixed height but direction is opposite i.e., initially in the upward direction and finally in the downward direction.
https://tex.z-dn.net/?f=%5Ctherefore%20%5Cdfrac%7B-u-u%7D%7B3.4%7D%3D%20-9.8%5C%5C%5CRightarrow%20%5Cdfrac%7B2u%7D%7B3.4%7D%3D%209.8%5C%5C%5CRightarrow%202u%20%3D%209.8%5Ctimes%203.4%5C%5C%5CRightarrow%20u%20%3D%20%5Cdfrac%7B9.8%5Ctimes%203.4%7D%7B2%7D%5C%5C%5CRightarrow%20u%20%3D%2016.67%5C%20m%2Fs
Hence, the particle was thrown with a speed of 16.67 m/s.
Now, we also note that the particle has zero velocity at its maximum height.
So, from the initial position to the maximum height reached by the particle, we have
https://tex.z-dn.net/?f=0%5E2%20%3D%20u%5E2%2B2as%5C%5C%5CRightarrow%20s%20%3D%20%5Cdfrac%7Bv%5E2-u%5E2%7D%7B2a%7D%5C%5C%5CRightarrow%20s%20%3D%20%5Cdfrac%7B0%5E2-16.67%5E2%7D%7B2(-9.8)%7D%5C%5C%5CRightarrow%20s%20%3D14.16%5C%20m
Hence, the maximum height reached by the ball is 14.16 m.
The jet engine of an airplane expels hot gas.
A. The airplane is propelled in the same direction as the hot gas.
B. The airplane is propelled in the opposite direction as the hot gas.
C. The airplane is propelled against the outside air.
Answer:
B. The airplane is propelled in the opposite direction as the hot gas.
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state the formula to compute average speed acquired by a vehicle to cover a distance between two points.
ty! :)
When a force is applied to a wheel, its axle exerts a greater force?
Answer:
That is true.
Explanation:
When the input force is applied to the wheel, as it is with a doorknob, the axle turns over a shorter distance but with greater force, so the mechanical advantage is greater than 1.
Fill in the blank with the correct response.
Light striking a mirror at a 45° angle will be reflected at a
how many electrons flow through a 3 A current in 3 seconds