Electromagnetic wave astronaut problem

AI Thread Summary
An astronaut, weighing 80 kg, has drifted 5.0 m from his space capsule and must use a 1000 W portable laser to propel himself back. The problem involves calculating the force exerted by the laser and the time it will take for the astronaut to reach the capsule. Key equations include the relationship between intensity, power, and area, as well as the momentum of the laser beam. The astronaut has a 10-hour oxygen supply, providing ample time for the calculations. The main challenge lies in determining the missing variables and applying the correct physics principles.
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Homework Statement

An 80 kg astronaut has gone outside his space capsule to do some repair work. Unfortunately, he forgot to lock his safety tether in place, and he has drifted 5.0 m away from the capsule. Fortunately, he has a 1000 W portable laser with fresh batteries that will operate it for 1.0 hr. His only chance is to accelerate himself toward the space capsule by firing the laser in the opposite direction. He has a 10-hr supply of oxygen.



Homework Equations


Intensity = P/A
F=ma
Electromagnetic wave F =q(E+ V x B)
E=cB

The Attempt at a Solution

I have tried to solve it for F but the thing is we don't have q and also there is a piece of equation that is missing and I don't know what it is since I couldn't find anything to relate in the book

Thanks
 
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What exactly are you supposed to calculate or find?
 
Oh, it's asking when the astronaut will reach the capsule
 
Looks like you'll need the momentum of the laser beam.
 
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