Question

A block is placed on a rough horizontal surface. The minimum force required to slide the block is

Answer 1

Answer:

Explanation:

A block resting on a horizontal surface and suppose a force is applied on it and still the body is not movinh then ,friction force is equal to applied force cancelling it

now when we increase the force to ,move the block then frictoinal force also increases

now according to maximum static friction ,the frictional force cannot cancel the applied force and the block starts to move.

so  

fsmac= μN

N=mg

so f smax= μmg

Answer 2

Given:

A block placed on horizontal surface

To Find:

Minimum force needed to slide the blck

Solution:

When we increase the force, the frictional force increases as well.  Thus,

fs (sliding friction) = μN

Now the friction force can not cancel the force applied and the block begins to shift according to the maximum static friction.

 N = Mg Thus,

fs = μMg

Thus, the minimum force required  will be = u times the weight  of block.

Answer: The minimum force needed is f smax = μmg