Question

A worker pulls horizontally on a crate across a rough horizontal surface, causing it to move forward with constant velocity. Force A is the force exerted by the worker and force B is the force of friction due to the surface. What is the relationship between A and B?
A > B
A = B
A< B
It will not slow down, but continue moving at constant velocity.

Answer 1

If an object is moving at a constant velocity ( That means a constant speed in a straight line. ) the net force acting on the object is zero, nothing. Why? It's motion is described by Newton's first law: An object at rest will remain at rest and an object in motion will remain in motion moving at constant velocity unless acted by an outside force.

Answer 2

Answer:

$A = B$

Explanation:

A work pulls the crate by horizontal force on it

Now due to this applied force crate is moving horizontally with uniform speed

so we can say that the acceleration of the crate will be zero

now by Newton's II law we can say

$F_{net} = 0$

$F - F_f = 0$

so here we will have

$F_f = F$

here we know that applied force is A

so F = A

and friction force is B

$F_f = B$

so correct relation is

$A = B$