Physics · Forces and Motion
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The body is moving with with momentum of 100 kg m/s. What is the magnitude of force required to stop this body in 25 seconds?
- A
4 N
- B
25 N
- C
100 N
- D
2500 N
The momentum of the body is given as 100 kg m/s, and the time taken to stop it is 25 seconds. To find the force required to stop the body, we can use the formula: Force = Change in Momentum / Time. Here, the change in momentum is equal to the initial momentum since the final momentum will be 0 when the body is stopped. Thus, Force = 100 kg m/s / 25 s = 4 N. This means that a constant force of 4 N is required to bring the body to rest in 25 seconds.
The other options are incorrect because they either imply an unrealistic time frame for stopping the body or do not correspond to the given momentum and time constraints.
This is the correct answer. To stop a body with a momentum of 100 kg m/s in 25 seconds, the required force is calculated as: Force = Momentum / Time = 100 kg m/s / 25 s = 4 N.
This option is incorrect. It suggests that a force of 25 N is required, which would imply stopping the body in only 4 seconds (100 kg m/s / 25 N = 4 s), not 25 seconds.
This option is incorrect. A force of 100 N would stop the body in just 1 second (100 kg m/s / 100 N = 1 s), which does not match the given time of 25 seconds.
This option is incorrect. A force of 2500 N would stop the body in a fraction of a second (100 kg m/s / 2500 N = 0.04 s), which is far less than the required 25 seconds.
Tagged under Physics · Forces and Motion · 2023