Newton's Second Law: Understanding Forces, Masses, and Acceleration

AI Thread Summary
During the collision between two trucks traveling at different speeds, the discussion revolves around the magnitudes of their accelerations. Initially, it was thought that the accelerations would be equal due to constant velocities, but the realization that both trucks decelerate during the collision led to confusion about their respective accelerations. The participants noted that according to Newton's Third Law, the forces acting on both trucks are equal and opposite, suggesting they would experience the same magnitude of acceleration. However, the impact of their different initial speeds and the type of collision (elastic or inelastic) also plays a crucial role in determining their post-collision velocities. Ultimately, the conversation emphasizes the relationship between forces, masses, and acceleration as outlined in Newton's Second Law.
NicholasJ
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Homework Statement


Two identical trucks traveling at different constant speeds are about to collide. The trucks are traveling in opposite directions with truck A going at a velocity of 3m/s right and truck B going at 4m/s left.

During the collision, will the magnitude of the acceleration of truck A be (a) greater than, (b) equal to, or (c) less than the magnitude of the acceleration of truck B?

Homework Equations

The Attempt at a Solution


I thought the answer would be (b) equal to, since they both travel at a constant velocity, but then I realized that during the collision they would be decelerating and so I think that it would be (c) less than, since truck A is going at a slower velocity than truck B and so it would decelerate less.

Can anyone tell me if I'm right or wrong and explain why? thanks
 
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What type of collision is being considered, elastic or inelastic? If elastic they will both move with different velocities after the collision. Of inelastic, they will both move off together at the same velocity.

Edit: Actually, I might suggest that you ponder the effects that Newton III will dictate for this collision (regardless of the type).
 
Last edited:
gneill said:
What type of collision is being considered, elastic or inelastic? If elastic they will both move with different velocities after the collision. Of inelastic, they will both move off together at the same velocity.

Edit: Actually, I might suggest that you ponder the effects that Newton III will dictate for this collision (regardless of the type).
Yea I think it's talking about the effects of Newton 3 since that's what we've covered in the lesson. But I am still unsure of how that relates to the magnitude of accelerations. Equal but opposite forces, so would they have the same acceleration?
 
NicholasJ said:
Yea I think it's talking about the effects of Newton 3 since that's what we've covered in the lesson. But I am still unsure of how that relates to the magnitude of accelerations. Equal but opposite forces, so would they have the same acceleration?
Yes. They have identical masses and the forces are always of the same magnitude. What does Newton II say about forces, masses, and acceleration?
 
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