In a two-vehicle non-central collision, the direction of force of at least one vehicle does not go through the center mass.

In a two-vehicle non-central collision, the direction of force of at least one vehicle does not go through the center mass.

• A. The force aligns precisely with the center of mass of both vehicles
• B. The force is zero and causes no damage
• C. The direction of force of at least one vehicle doesn't go through the center mass
• D. The collision results in simultaneous center-of-mass alignment

Answer: (C)

In a collision, how the force acts relative to a vehicle’s center of mass determines whether the vehicle will rotate. If the impact’s line of action passes through the center of mass, there is no torque about that center, so the vehicle would move in translation only. If the impact is off-center, the force does not go through the center of mass, creating a torque that causes rotation in addition to any forward or backward motion. In a two-vehicle non-central collision, at least one vehicle is struck off-center, so the direction of the force for that vehicle does not pass through its center of mass. That off-center impulse is what leads to rotational motion, making the statement correct. The other notions—force having to pass through the center of mass, the force being zero, or a special simultaneous alignment of centers of mass—don’t describe what typically happens in a non-central collision.

In a collision, how the force acts relative to a vehicle’s center of mass determines whether the vehicle will rotate. If the impact’s line of action passes through the center of mass, there is no torque about that center, so the vehicle would move in translation only. If the impact is off-center, the force does not go through the center of mass, creating a torque that causes rotation in addition to any forward or backward motion. In a two-vehicle non-central collision, at least one vehicle is struck off-center, so the direction of the force for that vehicle does not pass through its center of mass. That off-center impulse is what leads to rotational motion, making the statement correct. The other notions—force having to pass through the center of mass, the force being zero, or a special simultaneous alignment of centers of mass—don’t describe what typically happens in a non-central collision.