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vee123
Dec9-04, 04:41 PM
I am currently in AP Physics and we are studying centripetal force. My teacher gave me a problem that is driving me crazy because I don't know where to begin with it, and I have a test tomorrow...

Here's the problem:

An airplane pulls out of a dive in a vertical circle of radius 1.0 km traveling with a speed of 550km/h. How many times greater is the apparent weight of the pilot than his true weight?

Can someone please help me?

Parth Dave
Dec9-04, 05:56 PM
The true weight would be your weight if you were standing on the surface of the earth. This is because your weight is the normal force acting on you. If you were just standing on the surface, the normal force would oppose gravity which is the only other force acting on you. Thus, your weight would be the force of gravity, mg. In this situation, why would that be any different?

NateTG
Dec9-04, 06:42 PM
I am currently in AP Physics and we are studying centripetal force. My teacher gave me a problem that is driving me crazy because I don't know where to begin with it.

Here's the problem:

An airplane pulls out of a dive in a vertical circle of radius 1.0 km traveling with a speed of 550km/h. How many times greater is the apparent weight of the pilot than his true weight?

Any suggestions?

Here's another hint: It's important where in the loop the plane is (does the question specify that?)

vee123
Dec9-04, 07:57 PM
It doesn't specify where in the loop the plane is. I just want to know how to get through this problem. I'm so confused! :(

futb0l
Dec10-04, 12:36 AM
F = ma_c


and

a_c = v^2/r

so the ratio between the centripetal Force and the normal weight 9.8m is

\frac{m(v^2/r)}{9.8m} = \frac{1980000000}{1000*9.8} = 19800