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.
Coletrain12
Messages
16
Reaction score
0

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.
 
Physics news on Phys.org
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.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
Thread 'Voltmeter readings for this circuit with switches'
TL;DR Summary: I would like to know the voltmeter readings on the two resistors separately in the picture in the following cases , When one of the keys is closed When both of them are opened (Knowing that the battery has negligible internal resistance) My thoughts for the first case , one of them must be 12 volt while the other is 0 The second case we'll I think both voltmeter readings should be 12 volt since they are both parallel to the battery and they involve the key within what the...
Thread 'Trying to understand the logic behind adding vectors with an angle between them'
My initial calculation was to subtract V1 from V2 to show that from the perspective of the second aircraft the first one is -300km/h. So i checked with ChatGPT and it said I cant just subtract them because I have an angle between them. So I dont understand the reasoning of it. Like why should a velocity be dependent on an angle? I was thinking about how it would look like if the planes where parallel to each other, and then how it look like if one is turning away and I dont see it. Since...
Back
Top