A body thrown upwards with some external force

AI Thread Summary
A 1 kg ball is released and immediately hit by an upward force of 100 N, prompting the question of how high it will rise. The discussion highlights that to determine the height, one must consider the impulse generated by the force, which requires knowledge of the time duration the force is applied. It is noted that while the force indicates acceleration, it does not provide sufficient information to calculate the final velocity or height without additional data. The concept of impulse, measured in Newton-seconds, is emphasized as crucial for understanding the problem. Overall, the problem lacks enough information for a definitive answer.
Anjum S Khan
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Homework Statement


A ball of mass of 1Kg is held in hand. The moment it is released from hand, without any delay it is hit by an external force of 100N in upwards direction. How high will the body go ?

Homework Equations

The Attempt at a Solution


I know how to solve if instead of Force we consider initial velocity, then it becomes a standard problem.
 
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Did this problem come from a textbook? Or is it a problem you came up with on your own?

As it stands, there is not enough information to answer the question.
 
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This sounds like an impulse problem:
From (https://en.wikipedia.org/wiki/Newton's_laws_of_motion#Newton.27s_second_law)

"Impulse
An impulse J occurs when a force F acts over an interval of time Δt, and it is given by:
31f32d40451a63d365447185488faed9.png

Since force is the time derivative of momentum, it follows that
b3e1de85baa1adfe7dc442e69b93b45e.png

This relation between impulse and momentum is closer to Newton's wording of the second law.
Impulse is a concept frequently used in the analysis of collisions and impacts."

This should tell you what the instantaneous change in velocity should be from in impulse of 100N.
 
jbriggs444 said:
Did this problem come from a textbook? Or is it a problem you came up with on your own?

As it stands, there is not enough information to answer the question.
I created it on my own.
 
Anjum S Khan said:
I created it on my own.
Knowing the upward force is not enough to know how fast an object will move. It can tell you how fast the object will accelerate. In order to know how fast it will move, you must also know for how long the force is applied.
 
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RUber said:
This should tell you what the instantaneous change in velocity should be from in impulse of 100N.
Except that impulse is not measured in Newtons. It is measured in Newton-seconds.
 
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