Question

a crate is pulled forward with 200 n of force, which results in the crate maintaining a constant velocity of 5 m/s. what is the frictional force acting on the crate?
a 1,000 n
b 200 n
c 500 n
d 40 n

Explanation:

Step1: Analyze the motion state

When the crate is moving at a constant velocity, it is in equilibrium. According to Newton's first law, the net force \(F_{net}\) acting on it is \(F_{net}=0\).

Step2: Set up the force equation

Let the pulling force be \(F = 200\space N\) and the frictional force be \(f\). Since \(F_{net}=F - f=0\) (because the forces are in opposite directions along the line of motion), we can solve for \(f\).
From \(F - f = 0\), we get \(f=F\).

Answer:

B. \(200\space N\)