To solve for the magnitude of the force of friction on the sled, we can use the concept of equilibrium since Ancilla pulls the sled at a constant velocity. When an object moves at constant velocity, the net force acting on it is zero, according to Newton's first law of motion.
Given:
- Force applied (F_pull) = 200 N [E]
- Mass of the sled (m) = 38 kg
- The sled is moving at constant velocity, meaning the net force is 0 N.
Since the sled is being pulled horizontally and moving at a constant velocity, the force of friction (F_friction) must exactly balance the force applied. This means:
\[ F_{\text{pull}} = F_{\text{friction}} \]
Plugging in the given value:
\[ F_{\text{friction}} = 200 , \text{N} \]
Thus, the magnitude of the force of friction on the sled is 200 N.