Two crates are dropped from the same height in a vacuum. The mass and force of the crates are shown in the diagram. Which of the following statements is supported by the data?
a
The momentum of both crates will be the same right before they hit the ground.
b
The normal force will be the same on both crates when they hit the ground.
c
Both of the crates are accelerating at the same rate.
d
Both of the crates are falling at a constant speed.
The correct answer is (c) Both of the crates are accelerating at the same rate.
In a vacuum, there is no air resistance, which means that both crates will experience the same gravitational force and will accelerate at the same rate (9.8 m/s^2). The momentum of each crate will not necessarily be the same because momentum depends on both mass and velocity. The normal force on each crate will not be the same because the force of the crates hitting the ground will depend on their mass. The crates will not be falling at a constant speed because they will be accelerating due to gravity.