what two stars alternate every 13,000 years as earth’s northern star?

A control volume is a system that  always has a constant volume

What does "control volume" refer to?

A control volume is a volume of interest for a specific analysis in space. The control surface, which is a closed surface, is the surface of the control volume. A coordinate system that may be fixed, moving, or rotational is used to define the surface.

A control volume is a set area of space that is used to examine mass and energy balances for flowing systems using thermodynamics. An actual or hypothetical envelope may serve as the control volume's boundary. The control volume's perimeter is defined by the control surface.

To learn more about volume use link below:

https://brainly.com/question/28058531

#SPJ4

17,14mas should be used to maintain exposure.

Describe an Xray.

Electromagnetic waves are a category of radiation that includes X-rays. Using X-ray imaging, your body's interior can be visualized. The photos depict the various bodily parts in various shades of black and white. This is due to the fact that various tissues absorb radiation in different ways.

Keep your distance from any source of x-ray radiation at least 6 feet (2 meters). Distance considerably reduces radiation. If not necessary, walk away from the x-ray equipment. It is safe to live or work close to an x-ray room if it is in a building that complies with x-ray rules.

40/X =21000/9000

17.14mas = X

To learn more about radiation use link below:
https://brainly.com/question/1408043

#SPJ4

The company handbook is using Newton's first law and second laws of motion to ensure the safe and efficient movement of heavy bedroom furniture.

By removing the drawers from the dressers before moving them down the stairs, the company is reducing the mass of the object being moved, making it easier to handle in accordance with Newton's first law of motion, which states that 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 external force. By lifting the dressers instead of dragging them, the company is reducing friction, which can cause the dressers to slow down or stop, and making it easier to move the dressers in accordance with Newton's second law of motion, which states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass.

Learn more about Newton's first law  here

https://brainly.com/question/28278112

#SPJ4

Retrograde motion refers to the apparent backward movement of a planet in the sky as viewed from Earth. The direction of this retrograde motion is towards the west.

During this time, a planet appears to move against the background of the stars, which form the zodiac. This is because of the relative motions of Earth and the planet in question. Earth is moving in its orbit around the Sun faster than the other planet, causing it to overtake the other planet and give the illusion of it moving backwards. The retrograde motion is an optical illusion, and the planet continues its normal motion in its orbit around the Sun.

Learn more about Retrograde motion:

brainly.com/question/29823621

#SPJ4

Moon is moving away by 3.8 centimeters every year from the earth.

Because of its power of attraction, the moon pulls specific pieces of the Earth nearer to it more emphatically, making the flowing lump in the expanses of our planet. Since the Earth pivots a lot quicker than the moon, this lump happens somewhat in front of the last option, which, because of various actual peculiarities, drives the moon into a higher circle around Earth.

It's hazardously simple to underestimate the moon. Exactly the same thing is valid for the sun. In any case, if not for their everlasting presence in our skies, life on Earth would be extremely, not quite the same as what it is presently, and it wouldn't be an especially charming thing for us!

Notwithstanding, our main natural satellite - the moon - is really creating some distance from Earth. Its circle is getting bigger consistently!

To know more about moon,visit here:

https://brainly.com/question/2424777

#SPJ4

The wavelength of a wave moving at 450m/s with a frequency of 464Hz is 0.97m.

We know that wavelength of a wave is calculated by

[tex]\lambda=\frac{v}{f}[/tex]  ...(i)

where λ ⇒ wavelength

v ⇒ velocity of a wave

f ⇒ frequency

Now, as per the question:

Velocity of wave, v = 450 m/s

Frequency, f = 464 Hz

Putting the values in equation (i),

λ = 450/464

λ = 0.97 m

Therefore, wavelength of a wave moving at 450m/s with a frequency of 464Hz is 0.97m.

Read more about wavelength:

https://brainly.com/question/12924624

If an object is thrown straight down with the same speed, the time it takes to reach the ground depends on the height from which it was thrown and can be calculated using the formula [tex]t = sqrt(2h/g)[/tex]  where t is the time, h is the height, and g is the acceleration due to gravity, which is approximately equal to [tex]9.8 m/s^2[/tex] near the surface of the Earth.

If the object is thrown straight down with the same speed, it means that has zero initial velocity. In this case, the height h is simply the height from which the object was thrown.

Therefore:

[tex]t = sqrt(2h/g)[/tex]

To know more about Speed, here

https://brainly.com/question/28224010

#SPJ4

The speed of the stone when it reaches a height of 13.0 m is

GIven:

To calculate the speed one it reaches a certain height, we can use the formula as follows:

  Vt² = V0² - 2*g*s

In the case above, V0 = 27 m/s and the s is 13 m. Plug these numbers to the formula above:

  Vt² = V0² - 2*g*s

  Vt² = 27² - 2 * 9.8 * 13

  Vt² = 729 - 254.8

  Vt² = 474.2

Therefore,

  Vt = √474.2

  Vt = 21.776 m/s

Learn more about calculating speed at https://brainly.com/question/4581270

#SP4

The charge on a is 2.6 x 10⁻⁷ C when objects a and b are both positively charged. The initial acceleration of a is 4.2 x 10⁻⁶ m/s².

Like all forces, electric force is a vector quantity where the direction depends on the charge's sign and the magnitude can be calculated by the equation: F=q*E where the SI units are: q measured in coulombs (C), E is measured in Newton per coulomb (N/C) and F is measured by Newton (N)

Let's call the charge on object "a" "Qa" and the charge on object "b" "Qb". We know that Qb = 0.5 Qa.

From Coulomb's Law, the electric force experienced by object "b" can be expressed as:

F = k * (Qa * Qb) / r²

where k is the Coulomb constant (8.99 x 10⁹ Nm²/C²), r is the distance between the objects (10 cm = 0.1 m), and Qa and Qb are the charges on objects "a" and "b", respectively.

We can use the equation above to solve for Qa:

0.45 N = (8.99 x 10⁹ Nm²/C²) * (Qa * 0.5Qa) / (0.1 m)²

Expanding and solving for Qa:

0.45 N = (8.99 x 10⁹ Nm²/C²) * (0.25Qa²) / (0.1 m)²

0.45 N * (0.1 m)² / (8.99 x 10⁹ Nm²/C²) = 0.25Qa²

Qa = sqrt( (0.45 N * (0.1 m)² / (8.99 x 10⁹ Nm²/C²)) / 0.25 )

(a) Charge on "a" is Qa = sqrt( (0.45 N * (0.1 m)² / (8.99 x 10⁹ Nm²/C²)) / 0.25 ) = 2.6 x 10⁻⁷C

(b) To find the initial acceleration of "a", we need to find the force acting on it due to "b". This can be found using Coulomb's law:

F = k * (Qa * Qb) / r² = k * (Qa * 0.5Qa) / r² = 4.2 x 10⁻⁷ N

Since "a" has a mass of 100 g = 0.1 kg, the initial acceleration of "a" can be found as follows:

a = F / m = 4.2 x 10⁻⁷ N / 0.1 kg = 4.2 x 10⁻⁶m/s²

To know more about charge visit:-

https://brainly.com/question/14769922

#SPJ4

Question:

Objects a and b are both positively charged. both have a mass of 100 g, but a has twice the charge of b. when a and b are placed 10 cm apart, b experiences an electric force of 0.45 n. (a) what is the charge on a? (b) if the objects are released, what is the initial acceleration of a?

The density, in kilograms per cubic meter, of the woman is 958kg/m3 .

What does density means?

Density is a measure of the mass of a substance per unit volume. It is a measure of how closely packed the particles that make up a substance are. In other words, density can be thought of as a measure of how much matter is contained in a given volume. It is an important physical property of many materials, used to compare and identify them. An example of density would be the density of water. The density of water is 1 gram per cubic centimetre, meaning that one cubic centimeter of water weighs one gram.

It is given that woman floats in freshwater with 4.2 % of her volume above the surface of the water.

Therefore

[tex]\frac{Vwater.displaced}{ Vwoman} = \frac{100 - 4.2}{100 } =\frac{ 95.8}{100 }[/tex]

Putting this value in equation 1

1000kg/m3*  [tex]\frac{95.8 }{ 100}[/tex] = P woman

P woman = 958kg/m3

Therefore, 958kg/m3 is the answer.

To learn more about density from the link

https://brainly.com/question/29775886

#SPJ4

Answer:

the ancer is c I know it because I had the same test or it might have been different but it looks familiar to me

The net charge on the inner surface of the conductor is 3q, since the charge placed in the cavity adds to the existing charge, creating a net charge of 3q.

The net charge on the outer surface of the conductor is -2q, since the outer surface does not receive any new charge from the cavity and remains at -2q.

The net charges on the inner and outer surfaces of the conductor can be used to calculate the electric field outside the conductor and the electric potential inside the conductor. The electric field outside the conductor is determined by the net charge on the outer surface, while the electric potential inside the conductor is determined by the net charge on the inner surface. Additionally, the electric field outside the conductor can also be used to calculate the capacitance of the conductor, which is the measure of the amount of charge it can store.

Learn more about net loads :

https://brainly.com/question/26552744

#SPJ4

The sailor must sail a distance of 102.0 km to reach the original destination and the sailor must sail in a direction 53.13° east of north to reach the original destination.

(a) To find the distance the sailor must sail to reach the original destination, we can use the Pythagorean theorem. Let's call the distance the sailor must sail "d". Then, we have:

[tex]d^2 = 50^2 + 90^2[/tex]

d = sqrt(2500 + 8100) = sqrt(10600) = 102.0 km

So, the sailor must sail a distance of 102.0 km to reach the original destination.

(b) To find the direction in which the sailor must sail, we can use trigonometry. Let's call the angle between the direction of sailing and the direction towards the original destination "θ". Then, we have:

tan(θ) = 50 / 90 = 5/9

[tex]θ = tan^-1(5/9) = 53.13°[/tex]

So, the sailor must sail in a direction 53.13° east of north to reach the original destination.

Learn more about distance here

https://brainly.com/question/2734924

#SPJ4

The minimum thickness of the film is 169.35 nm.

Wave interference is when two waves collide while traveling through the same medium. A wave is a point-by-point combination of two waves. Constructive interference occurs when the resulting wave is larger than either source wave. Destructive interference occurs when the resulting wave is smaller than the two source waves. Initial wavelength = π due to dense medium.

Δφ1 = π (4dnb/λ)

The minimum thickness of the film is reached after the result is calculated as

Δφ12 = Δφ1 − Δφ2 

d= [tex]\frac{525}{3.1}[/tex]

d= 169.35 nm

Minimum thickness of the film will be 169.35 nm.

Learn more about wave

brainly.com/question/956133

#SPJ4

The relationship between the force and the electric field is described by Coulomb's law is F = qE.

The relationship between the force and the electric field is described by Coulomb's law, which states that the force experienced by a point charge in an electric field is proportional to the magnitude of the charge and the electric field. Mathematically, Coulomb's law can be expressed as:

F = qE

where F is the force experienced by the point charge (q), E is the electric field, and q is the magnitude of the charge.

Conceptually, the electric field can be thought of as a field of force that is created by charged particles. A point charge placed in this field experiences a force proportional to both the magnitude of the charge and the strength of the field. This relationship between the electric field and the force experienced by a point charge forms the basis of Coulomb's law.

Learn more about magnitude here

brainly.com/question/28173919

#SPJ4

The electric field will be along the left direction.

An electric field is a region around the charge where its force of attraction or repulsion can be measured.

Given is the equipotential surface as shown in the image attached.

We know that electric field is the negative gradient of electric potential.

We can write -

E = - dV/dx

- dV = E dx

dV = - E dx

V = - ∫E dx

So, the electric field will be along the left direction.

Therefore, the electric field will be along the left direction.

To solve more questions on Electric fields and potentials, visit the link below -

brainly.com/question/25384702

#SPJ1

The final charge state of each sphere and the rod is observed to be neutral state.

Initially, the two spheres and the metal rod are not in contact. As, all the three objects are made of metal, they are charge and electricity conductors.

As the spheres have an equal amount of opposing charge when they come in contact with neutral metal rod, electrons transfer from negatively charged sphere to positively charged sphere through the metal rod until the whole system reaches electrostatic equilibrium.

Due to an equal quantity of opposite charge in the initial state, the system will be in a neutral state.

When there is a constant between two spheres over a metal rod and electrons, the system as a whole has neutral charge.

To know more about charge:

https://brainly.com/question/16965473

#SPJ4

Answer:

Joule, a 19th-century physicist, believed in the conservation of energy, which contradicted the beliefs of his peers at the time. His contemporaries believed that energy was a substance that could be created or destroyed. In contrast, Joule believed that energy could only be transformed from one form to another but could never be created or destroyed. He demonstrated this through a series of experiments where he showed that heat and mechanical work were equivalent forms of energy and that the total amount of energy in a closed system remained constant.

Joule's ideas challenged the established scientific beliefs of his time. They paved the way for the development of the first law of thermodynamics, which states that the total energy in a closed system is constant and cannot be created or destroyed. By proposing and demonstrating these ideas, Joule made significant contributions to the development of classical physics and helped lay the foundations of modern energy science.

Answer:

James Prescott Joule was a 19th-century British physicist who made significant contributions to the study of thermodynamics. One of his beliefs that contradicted the beliefs of his peers was the idea that heat was a form of energy.

At the time, the prevalent belief was that heat was a fluid-like substance called "caloric" that flowed from hot objects to cold objects. Joule challenged this idea and proposed that heat was actually a form of energy that could be transformed into other forms of energy, such as mechanical energy.

Joule's work showed that heat was a conserved quantity, much like energy, and that it could be quantified in terms of work done. This was a significant departure from the prevailing ideas of the time and helped lay the foundation for the study of thermodynamics.

The capacitance across the motor must be 86.87 f to increase the power factor to 0.9 lagging.

An electric rotating machine with the capacity to transform electrical energy into mechanical energy is known as a single-phase motor. It functions using a single-phase power source. They have hot and neutral wiring, respectively. Their supply voltages fluctuate in unison and their power can exceed 3Kw.

I1 = 20A, f = 50 Hz

cosϕ1 = 0.75 ⇒ ϕ1 = 41.41∘ ⇒ tanϕ1 = 0.88

cosϕ2 = 0.9 ⇒ ϕ2 = 25.84∘ ⇒ tanϕ2 = 0.48

Ic = I1 cosϕ1 (tanϕ1 − tanϕ2)

= (20) (0.75) (0.88 – 0.48) = 6 A

C = Ie/2πfv

C = 6/2π × 20 × 220

C = 86.87∪f

To know more about capacitance visit:-

https://brainly.com/question/28445252

#SPJ4

The vertical component of velocity shortly before the stone reaches the ground equals the original vertical velocity ie, v m/s

The vertical component of an object's velocity right before impact can be computed using equations of motion. If we examine a gravity-affected item with a beginning velocity (v0) and no air resistance, its vertical velocity (v) may be given by the equation:

v = v0 - gt

where g is the gravitational acceleration (9.8 m/s2) and t is the time since the item was launched.

To calculate the vertical component of velocity immediately before the stone reaches the ground, we must first compute the time t required for the stone to reach the ground. The following equation may be used to compute this:

t = (v0 - v) / g

By reintroducing the value of t into the first equation, we obtain:

v = v0 - gt = v0 - g((v0 - v) / g) = v0 - (v0 - v) = v

It is crucial to note that this estimate assumes no air resistance and that the object is dropped from a height far lower than the radius of the Earth, allowing the curvature of the Earth to be ignored. In fact, air resistance may have a major impact on an object's velocity, particularly as it approaches the earth.

For more such questions on velocity, click on:

https://brainly.com/question/25905661

#SPJ4

The ballplayer's speed when making the catch is 0.049 m/s. If the 140 g ball is travelling 27 m/s in a horizontal direction.

Galileo Galilei, an Italian physicist, is credited with being the first to calculate speed by dividing it by the distance travelled and the time required. Galileo defined speed as the amount of distance travelled in a given amount of time.

Speed with a direction is called velocity. A speed is defined as 9 km/h (kilometres per hour) for Ariel the Dog. Yet, stating that he runs 9 km/h westwards is a speed. Think about anything that is moving quickly back and forth but has a low (or zero) velocity

Therefore, If the 140 g ball is moving at 27 m/s in a horizontal direction, the ballplayer's speed when making the catch is 0.049 m/s.

Learn more about ballplayer here:

https://brainly.com/question/17020445

#SPJ4

Answer:

A hair dryer converts electrical energy into thermal and then sound energy.

The molecular motion of  the water particles as the burner supplies heat is convection current of heat.

Convection is a single- or multiphase fluid movement that develops on its own as a result of the interaction between a fluid's body forces—most frequently gravity and density—and material property heterogeneity.

It is safe to presume that convection will occur as a result of thermal expansion and buoyancy when the reason of the convection is unknown. Convection may also occur in mixes or soft materials where particles can move.

Learn more about convection here:

https://brainly.com/question/4138428

#SPJ1

At absolute zero temperature, all molecules of a fluid would have zero kinetic energy and would be at rest. Therefore, the fluid would exert zero pressure on its system container.

This is because pressure arises due to the collision of molecules with the walls of the container, and at absolute zero temperature, there is no molecular motion or collision. At absolute zero temperature, there is no molecular motion or collision, and therefore, there can be no pressure. The molecules are frozen in place, and they cannot exert any force on the walls of the container. This means that the pressure of the fluid is zero at absolute zero temperature.

To know more about Pressure, here

https://brainly.com/question/29341536

#SPJ4

The tangential component of acceleration is calculated to be 8.66 ft/s² and the radius of curvature is 1280 ft.

The tangential acceleration is known to be a measure of the rate of change in the magnitude of a velocity vector.

Speed of the automobile = 80 ft/s

Acceleration of the automobile a = 10 ft/s²

Construct a triangle with 30°, 60°, 90° with vector a as the hypotenuse, t and n as the legs.

an is the centripetal acceleration along n direction.

at is the tangential acceleration along t direction.

sinθ = an/a

an = a sinθ = 10 sin30° = 10(1/2) = 5 ft/s²

cosθ = at/a

at = a cosθ = 10 cos30° = 10(1/√2) = 10(0.866) = 8.66 ft/s²

From centripetal acceleration, we know,

an = v²/r

r = v²/an = 80²/ 5 = 1280 ft

Thus, the tangential component of acceleration is 8.66 ft/s² and the radius of curvature is 1280 ft.

The given question is incomplete without the figure. It is given in the attachment below.

To know more about tangential acceleration:

https://brainly.com/question/14748871

#SPJ4

In this case, the electric field in that area will cause a charged particle to experience a force in the direction of the increasing electric potential if it is discharged at a position with a lower electric potential.

Zero There is no direction of greatest increase if the electric potential is constant. Therefore, anywhere inside the region of continuous electric field, the electric field is zero and the gradient of the electric potential is also zero.

Only the x coordinate, where a and b are constants, determines the field potential in a specific area of space. Discover the space charge's Q(x) distribution. As V=ax3+b, the electric field potential at a given location in space only depends on the x coordinates.

To know more about electric potential visit:-

https://brainly.com/question/12645463

#SPJ4

The connection of three strings of patio lights, One whole string does not light, but all bulbs in the other two strings do three strings are connected in series, while each string's bulbs are connected in parallel.

The voltage across each component in a parallel connection is equal to voltage throughout the network, despite each component being connected via a different path.

The three strings are connected in series, while each string's bulbs are connected in parallel. The remaining strings of bulbs will continue to glow even if one bulb in a string fails.

Therefore, three strings are connected in series while each string's bulbs are connected in parallel.

To know more about the parallel connection, here

brainly.com/question/82566

#SPJ4

It will take Xavier 1 hour to catch up with Pedro.

To find the time it takes for Xavier to catch up with Pedro, we need to determine how far Pedro will travel during that time. Let's call this distance "d". We know that Pedro is traveling at a speed of 18 km/hr, so we can use the formula distance = speed x time to find d: d = 18t. At the same time, Xavier is closing the gap between himself and Pedro at a speed of 24 km/hr, so the total distance between them is decreasing at a rate of 24 km/hr + 18 km/hr = 42 km/hr.

Thus, the distance between Xavier and Pedro is decreasing at a rate of 42t km/hr. Setting the two distances equal, we have 18t = 1/2 + 42t. Solving for t, we find that t = 1 hour. So, it will take Xavier 1 hour to catch up with Pedro.

Learn more about Speed Distance Time:

https://brainly.com/question/26046491

#SPJ4

A mass of 5 lb is acted upon by an upward force of 16 lb. the only additional force on the mass is the force of gravity. The acceleration is -29 ft/[tex]s^{2}[/tex], which is downward.

The net force on the 5 lb mass is equal to the difference between the upward force and the force of gravity. The force of gravity can be calculated as follows:

fgravity = m . g

where,

m = 5 lb (mass)

g = 32.2  ft/[tex]s^{2}[/tex] (acceleration due to gravity)

So,

fgravity = 5 lb * 32.2  ft/[tex]s^{2}[/tex] = 161 lb

The net force on the mass can then be calculated as follows:

fnet = fupward - fgravity = 16 lb - 161 lb = -145 lb

Since the net force is negative, it acts in the downward direction. To calculate the acceleration, we use Newton's second law of motion:

f = ma

where,

m = 5 lb (mass)

a = acceleration

Solving for acceleration, we get:

a = fnet / m = -145 lb / 5 lb = -29  ft/[tex]s^{2}[/tex]

So, the acceleration is -29  ft/[tex]s^{2}[/tex], which is downward.

Here you can learn more about Net acceleration

brainly.com/question/30432236

#SPJ4

The magnitude of the force that particle b exerts on particle a is 0.86 N. To find the vector force, we need to determine the direction of the force. Since particle b is moving directly away from particle a, the force it exerts on particle a is in the opposite direction, i.e., to the left. Therefore, the vector force is -0.86 N in the x-direction.

Force is an interaction between two objects that occurs when one object exerts a push or pull on the other. Forces can cause objects to accelerate, decelerate, or change direction. In classical mechanics, the force is described by Newton's second law of motion, which states that the rate of change of momentum of an object is proportional to the applied force.

We can use Coulomb's Law to calculate the magnitude of the force between the two charged particles:

[tex]\mathrm{F = k \times q_1 \times q_2 / r^2}[/tex]

where F is the force, k is the Coulomb constant, q1 and q2 are the charges of the particles, and r is the distance between them.

Let's assume that particle a has a positive charge and particle b has a negative charge. Then, we can write the following equation based on the information given:

[tex]\mathrm{2.38 N = k \times q_1 \times q_2 / (12.9 mm)^2}[/tex]

We also know that the distance between the particles increases to 18.2 mm. Since particle b moves away from particle a, the direction of the force it exerts on particle a is opposite to the direction of the force that particle a exerts on particle b.

To calculate the magnitude of the force that particle b exerts on particle a, we can use the same equation and substitute the new distance:

[tex]\mathrm{F' = k \times q_1 \times q_2 / (18.2 mm)^2}[/tex]

Since the charges q1 and q2 are the same, we can simplify the equation as follows:

F' = F × (12.9 mm / 18.2 mm)²

F' = 2.38 N × (0.709 mm / 1.0 mm)²

F' = 0.86 N

The magnitude of the force that particle b exerts on particle a is 0.86 N. To find the vector force, we need to determine the direction of the force. Since particle b is moving directly away from particle a, the force it exerts on particle a is in the opposite direction, i.e., to the left. Therefore, the vector force is -0.86 N in the x-direction.

To learn more about force from given link

https://brainly.com/question/13191643

#SPJ4