(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An astronaut (mass mA) in space, tied to the end of a tether of length 10m, is traveling in a circle with constant speed making one revolution every 15seconds.

a) Assume that the astronaut fires a spring loaded gun (containing a ball) towards the center of the circle and when he is located at the origin. Sketch the trajectory of the ball as seen by someone fixed in space. (Overheard perspective)

b) If the gun is directed towards the center of the circle, then regardless of the speed of the ball the astronaut cannot catch the ball. Explain why this is so.

c) Is there any circumstance for which the astronaut can fire the gun and catch the ball? Explain.

2. Relevant equations

Fc = mv^2/r

3. The attempt at a solution

I'm working on this in a group. The general consensus for part A is that the trajectory of the ball will go diagonally off to the right (assuming he is traveling counter-clockwise). Of course I've heard arguments that make sense to me for the ball just going straight to the other side of the circle, and for the ball going at a curve to the right. I got to admit I find it very confusing.

For part b I think we have it in our mind, due to the circle the astronaut has to take and the balls singular direction, but not really sure how to formulate it into a coherent sentence. As for part c we think if he shot the ball at a certain critical angle he might be able to catch it.

Thanks before hand for any help you can offer! If you need to see the picture we have to sketch the trajectory on I can scan it in (though I don't find it all that helpful).

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# Homework Help: Astronaut With Gun and Circular Motion

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