Question

A crate is sitting in the center of a flatbed truck. As the truck accelerates to the east, the crate moves with it, not sliding on the bed of the truck. In what direction is the friction force exerted by the bed of the truck on the crate? 1. To the south 2. There is no friction force, because the crate isn’t sliding 3. To the west 4. To the east 5. To the north

Answer 1

4. To the east

Step-by-step explanation:

Friction forces always act in the opposite direction that an object tends to move in. In this case, when the truck accelerates to the east, the crate tends to move to the west due to inertia (the tendency for an object to remain at rest or at constant speed). In order to stop the crate from moving, there needs to be a friction force to the east.