Question

A clod of dirt falls from the bed of a moving truck. It strikes the ground directly below the end of the truck. What is the direction of its velocity relative to the truck just before it hits? Is this the same as the direction of its velocity relative to ground just before it hits? Explain your answers.

a) The direction of velocity relative to the truck is downward; relative to the ground, it is horizontal.

b) The direction of velocity relative to the truck is horizontal; relative to the ground, it is downward.

c) The direction of velocity relative to both the truck and the ground is downward.

d) The direction of velocity relative to both the truck and the ground is horizontal.

Answer 1

The velocity of the dirt relative to the truck is downward, while its velocity relative to the ground is horizontal.

Step-by-step explanation:

The direction of velocity relative to the truck just before it hits is downward. This is because the clod of dirt falls straight down due to gravity. However, the direction of velocity relative to the ground just before it hits is horizontal. This is because the truck is moving horizontally when the dirt falls and the dirt maintains that horizontal velocity until it hits the ground.