Mag of impulse required to change speed question.

AI Thread Summary
To determine the impulse required to increase a proton's speed from 0.995c to 0.998c, relativistic momentum must be considered due to the high speeds involved. The initial approach of using classical momentum equations is incorrect, as they do not account for relativistic effects. The correct method involves using the relativistic momentum formula, which incorporates the Lorentz factor. The discussion highlights confusion over the appropriate equations and the need for a deeper understanding of relativistic physics. Ultimately, the problem emphasizes the importance of using the correct framework for calculations at relativistic speeds.
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Homework Statement



A proton has mass 1.7x10-27 kg. What is the magnitude of the impulse required in the direction of motion to increase its speed from 0.995c to 0.998c? Where c is the speed of light.

Homework Equations



Im not quite sure of what equation is supposed to be used. I tried using (momentumfinal)=(momentuminitial) + Fnet*(changeintime)

The Attempt at a Solution



Ok my attempt at the problem is the only way i can think of it and the answer is still wrong. I first multiplied the speeds by the mass to get a momentum. Then used the two momentums and plugged them into the equation above and solved for Fnet*(changintime) which equals Impulse if I am not mistaken. I got the number 1.53e-21 for my answer.

The only problems i can think of is maybe those speeds are speeds(needs to be velocity).. and can't multiply by the mass to get a momentum but i don't see why that would cause a problem. Overall I am stumped on this problem and not sure why what I've done doesn't work. I even have talked to others in the class and no one can figure it out.

Thanks for all the help in advance guys.
 
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Considering how high the speed of the particle is, I wonder if you have to consider relativistic momentum?
 
Yes, 0.995c is definitely relativistic. mv will not work for calculating momentum.
 
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