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pychu [463]
2 years ago
7

Then it is called

Physics
1 answer:
DiKsa [7]2 years ago
8 0

Answer:

It is called force of friction

Explanation:

The force of friction is a force that acts between two objects whose surfaces are in contact with each other.

Consider the typical case of an object sliding along a certain surface. There are two types of frictions:

- Static friction: this is the force of friction that acts when the object is not in motion yet. If you push the object forward with a force F, the object will not move immediately, but it will "oppose" to this motion with a force of static friction exactly equal to the push applied:

F_f = F

However, this force of static friction has a maximum value, which is given by

F_{max} = \mu_s N

where

\mu_s is the coefficient of static friction

N is the normal reaction exerted by the surface on the object

So, when F becomes greater than F_{max}, the static friction is no longer able to balance the push applied, and the object will start sliding forward.

- Kinetic friction: this is the force of friction that acts when the object is already in motion. Its magnitude is given by

F_f = \mu_k N

where

\mu_k is the coefficient of kinetic friction, and its value is generally smaller than \mu_s. The direction of this force is also opposite to the direction of motion of the object.

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Answer:

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Explanation:

Given:

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Therefore, the power output of the first motor is 2\times 10^4\ W

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Answer:

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