Question

in which crash did the asteroid experience a stronger force? how do you know?
a crash 2: the force on the planet was stronger in this crash, so the force on the asteroid was also stronger.
b there was no force on the asteroid. only the moon and planet experienced a force in each crash.
c the diagram doesnt tell you anything about the force on the asteroid. it only gives information about the force on the planet and the moon.
d the force was the same in both crashes. the planet and moon changed speed by the same amount so that means the force on the asteroid was the same in both crashes.

Explanation:

According to Newton's third - law of motion, for every action, there is an equal and opposite reaction. In a collision between an asteroid and a planet (or moon), the force exerted on the asteroid is equal in magnitude and opposite in direction to the force exerted on the planet (or moon). If the force on the planet is stronger in one crash, the force on the asteroid in that same crash is also stronger as they are action - reaction pairs.

Answer:

A. Crash 2: the force on the planet was stronger in this crash, so the force on the asteroid was also stronger.