If you exert a horizontal force of 200 N to slide a crate across a factory floor at constant velocity, how much friction is exerted by the floor on the crate?

200 N

Explanation:

Applied force, F = 200 N

Let the friction force is f.

By use of Newton's second law

Net force = mass * acceleration

F - f = m * a

Here acceleration a is zero as crate moves with constant velocity.

So, F - f = 0

f = F

Friction force = 200 N