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Trigger
Nov17-04, 11:53 AM
Please help with the following problem:

Assume a monkey lets go of a tree when a tranquiliser is fired. At what angle should the gun be pointed so that the tranquiliser hits the monkey while in free fall?

Neglect size of gun and monkey. Let Xm,Ym = monkey's initial position, Vo=magnitude of tranquilizer's initial velocity. What is the minimum velocity, Vo(in m/s) so that the tranquilizer hits the monkey in free fall if Xm=Ym=10m?

What curve describes the tranquilizer's trajectory?Prove it

Doc Al
Nov17-04, 12:00 PM
Hint: What if there were no gravity?

Trigger
Nov17-04, 12:03 PM
need a better hint!

Doc Al
Nov17-04, 12:05 PM
Answer the question first!

Trigger
Nov17-04, 12:11 PM
If there were no gravity then the monkey would not experience an accelearation of 9.81 towards the centre of the earth and the bullet would not fall as it flies through the air also.

Physics_wiz
Nov17-04, 12:15 PM
Think outside the box.

Trigger
Nov17-04, 12:19 PM
Solved the first part of the problem, i.e angle=45 degrees. I realise that the tranquiliser should be fired at the monkey and not below it as the tranquiliser falls like the monkey but really need help to find the minimum velocity needed.
PLEASE HELP!

Physics_wiz
Nov17-04, 12:21 PM
Yep, you got it. So, the shot will hit the monkey no matter what (if it's directed at the monkey). The only problem now is to make the shot reach the monkey before he falls 10 m. Find the time it takes him to fall the 10 m and then see what minimum velocity you need for the tranquilizer to cover a distance of 10 m before the monkey falls.