All categories

2 years ago

How can Magnets cause objects to have kinetic energy?

Physics

2 answers:

Aleks04 [339]2 years ago

8 0

Answer:

Hi !!!!!!!!!

Here u go

100% confirm answer

If there is a system of magnets being held in place, there is potential energy. When you let go, the potential energy converts to kinetic energy and the magnets move. ... Putting the system of magnets close together which creates an opposing force.

PLEASE MARK ME AS BRAINLIST

<em />

lianna [129]2 years ago

4 0

Answer:

If there is a system of magnets being held in place, there is potential energy. When you let go, the potential energy converts to kinetic energy and the magnets move. Putting the system of magnets close together which creates an opposing force.

Explanation:

You might be interested in

PV = nRT, is the a. equation of state of an ideal gas

romanna [79]

Ideal gas law:

PV = nRT

P = pressure, V = volume, n = # of moles, R = gas constant, T = temperature

Equipartition theorem:

Each degree of freedom that a molecule has adds 0.5kT to its total internal energy where k = Boltzmann's constant and T = temperature

2nd law of thermodynamics:

A set of governing principles that restrict the direction of net heat flow (always hot to cold, heat engines are never 100% efficient, entropy always tends to increase, etc)

Clearly the answer is Choice A

3 0

3 years ago

Sort the forces as producing a torque of positive, negative, or zero magnitude about the rotational axis identified in part

Fantom [35]

a) Angular acceleration: $17.0 rad/s^2$

b) Weight: conterclockwise torque, reaction force: zero torque

Explanation:

In this problem, you are holding the pencil at its end: this means that the pencil will rotate about this point.

The only force producing a torque on the pencil is the weight of the pencil, of magnitude

$W=mg$

where m is the mass of the pencil and g the acceleration of gravity.

However, when the pencil is rotating around its end, only the component of the weight tangential to its circular trajectory will cause an angular acceleration. This component of the weight is:

$W_p =mg sin \theta$

where $\theta$ is the angle of the rod with respect to the vertical.

The weight act at the center of mass of the pencil, which is located at the middle of the pencil. So the torque produced is

$\tau = W_p \frac{L}{2}=mg\frac{L}{2} cos \theta$

where L is the length of the pencil.

The relationship between torque and angular acceleration $\alpha$ is

$\tau = I \alpha$ (1)

where

$I=\frac{1}{3}mL^2$

is the moment of inertia of the pencil with respect to its end.

Substituting into (1) and solving for $\alpha$ , we find:

$\alpha = \frac{\tau}{I}=\frac{mg\frac{L}{2}sin \theta}{\frac{1}{3}mL^2}=\frac{3 g sin \theta}{2L}$

And assuming that the length of the pencil is L = 15 cm = 0.15 m, the angular acceleration when $\theta=10^{\circ}$ is

$\alpha = \frac{3(9.8)(sin 10^{\circ})}{2(0.15)}=17.0 rad/s^2$

There are only two forces acting on the pencil here:

- The weight of the pencil, of magnitude $mg$

- The normal reaction of the hand on the pencil, R

The torque exerted by each force is given by

$\tau = Fd$

where F is the magnitude of the force and d the distance between the force and the pivot point.

For the weight, we saw in part a) that the torque is

$\tau =mg\frac{L}{2} cos \theta$

For the reaction force, the torque is zero: this is because the reaction force is applied exctly at the pivot point, so d = 0, and therefore the torque is zero.

Therefore:

- Weight: counterclockwise torque (I have assumed that the pencil is held at its right end)

- Reaction force: zero torque

8 0

3 years ago

A scientist pours grape juice on three identical white shirts. He then uses three different cleaning products on the shirts and

inysia [295]

The independent variable would be the cleaning products.

The independent variable is the variable that you can manipulate. The change in the independent variable is not affected by other variables. So in this case, the independent variable would be the cleaning product because you will be changing it.

3 0

3 years ago

Read 2 more answers

The speed of light in a vacuum is 299,792,458 m/s. Which gives this number in three significant digits? 299,000,000. m/s 2.99 x

dexar [7]

Answer: $2.99(10)^{-8} m/s$

Explanation:

When a number is written in scientific notation (representing the number using powers of base ten) it is expressed so that it contains a digit in the place of the units and all other digits after the decimal point, multiplied by the respective exponent.

Then, the significant figures (or significant digits) will be the digits that are before the power of ten.

Now, in the case of the number 299,792,458 if we want to write it with three significant digits, we have to write it in scientific notation as:

$2.99(10)^{-8}$

7 0

3 years ago

Read 2 more answers

Doppler effect is caused by sound or light wave being pushed together and spread apart due to motion. True or False.

pychu [463]

Answer: false.

Explanation:

Doppler effect is caused to the relative motion of the source of light/sound with respect to the observer.

If the source is moving towards you, you will perceive the frequency to be larger (also called a blue shift), while if the wave is moving away, you will perceive the frequency to be smaller (also called a red shift).

Then the statement:

"Doppler effect is caused by sound or light wave being pushed together and spread apart due to motion."

Is false

3 0

2 years ago