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mbradar2
Nov15-10, 11:21 PM
1. The problem statement, all variables and given/known data
Compute the speed of debris seen hitting the inner ring of Supernova 1987A. Assume radius of inner ring is 0.7 light years.

2. Relevant equations


3. The attempt at a solution
I'm not quite sure where to start. I thought about just using kinetic energy = 0.5mv^2 because I can find the total energy released on Wikipedia (10^46 J), but what would I put for m? Then I realized that way, I'm not using the radius that they gave me, so it's probably wrong. So...

I'd appreciate any guidance!

chemisttree
Nov16-10, 04:55 PM
Inner ring started travelling in 1987 and has reached a distance of 0.7 ly. You have time and distance. Can you calculate speed from that?

How about this problem... if it takes me an hour to travel 50 miles, how fast am I travelling?