Homework Question on Momentum
- To impart the greatest momentum to an object, should you exert the largest force possible, apply that force for the longest time possible, or both? Explain your reasoning.
- If a large truck and a small Smart Car have a head-on collision, which vehicle experiences the greater force of impact? The greater impulse? The greater change in momentum? The greater deceleration?
- As you throw a ball upwards, is there a change in the support force on your feet? Is there a change in the support force on your feet when you catch the ball? (Think of doing this while standing on a bathroom scale).
- Are there any specific concepts in chapter 6 that you found challenging or difficult and would like to review in class next week?
Homework Answer on Momentum
1.To impart the greatest momentum on an object, should you exert the largest force possible, apply that force for the longest time possible, or both? Explain your reasoning.
When an object moves, it has momentum since it has mass and it is in motion. These two variables are interdependent in determining the momentum of an object. To experience the greatest momentum on an object, you need to exert the largest impulse possible on an object. Impulse is defined by the acting force multiplied by the time taken to act on an object. Impulse increases by the same factor as time. The resulting impulse is equal to the momentum change. This aspect demonstrates a directly proportional relationship between momentum and impulse.
- If a large truck and a small Smart Car have a head-on collision, which vehicle experiences the greater force of impact? The greater impulse? The greater change in momentum? The greater deceleration?
The impact is a high force exerted over a very short time. It depends on the velocity of an object. Thus, the smaller car will have a greater impact. Newton’s third law of motion states that for two approaching bodies, their forces are equal but opposite in direction. Since the time of contact is the same for the two trucks, they will experience the same impulse. There will also be the same change in momentum for the truck and the car because it is directly proportional and equal to the impulse. The car will have a significant deceleration since it was in a high speed and promptly comes to a stop.