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Dropping the ball

  • Thread starter mrb112103
  • Start date
  • #1
3
0
So, here is the problem:

I have a .535kg ball that I drop from an unkown height, to create an impact with a force of 6.8 Joules.

I need to figure out what height to drop the ball from.

I figure it has something to do with accleration due to gravity and Netwons law F=mA or possibly a kinetic energy equation.

Right now I am scrambling to find the answer.

Can anyone please help?
 

Answers and Replies

  • #2
5,428
291
You need to define mathematically what 'impact' is. If you drop something it acquires momentum. A force is exerted when there's a change in the momentum, like when the dropped thing hits the ground. The force depends on how quickly the object stops. The faster it stops the greater the force.
 
  • #3
135
0
Well, if you define impact as energy, which is suggested by your units, then what you need to do is apply the Conservation of Energy. In your case, you wan't a KE of 6.8J, hence you can equtae it with potential energy.
 

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