# Homework Help: To set a swing going

1. May 24, 2010

### lisa1234

Is it impossible for me to to set a swing (on which a child weighing 66 pound is sitting) going, so that its velocity from the very beginning is 33 ft/s? Why/Why not?

I find myself quite lost with this question so I have no attempts at any solutions...all i know is that it sounds impossible to me..but i don't know how to prove it:S Maybe one could in some way use momentum p=m*v ...

Would really appreciate some help!:)

2. May 24, 2010

### tiny-tim

Welcome to PF!

Hi lisa1234! Welcome to PF!
Well, suppose the child, instead of being stationary on a swing, was stationary on the ground (say, on ice) …

could you then set the child moving at 33 ft/s ?

3. May 24, 2010

### lisa1234

No probably not...i mean it's almost impossible to even run that fast..
But aren't there any equations i can use to prove it??

4. May 24, 2010

### irycio

Well, try calculating the acceleration that would be needed to set anyone moving with any velocity in no time assuming that the velocity in the beginning was 0 :P. This advice is not as stupid as it seems to be ;)

5. May 24, 2010

### tiny-tim

What would happen if another child collided with it?