How Is the Momentum of an Electron Calculated at 0.8c?

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The momentum of an electron traveling at 0.8c cannot be accurately calculated using the classical equation p = mv, as this is only valid at low speeds. Instead, the relativistic momentum formula should be used: p = m0v/√(1-v²/c²), where m0 is the rest mass of the electron. At 0.8c, the relativistic effects become significant, necessitating this adjustment for accurate calculations. The discussion highlights the importance of using the correct equations when dealing with high-speed particles. Understanding these concepts is crucial for solving related physics problems effectively.
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Homework Statement


What is the magnitude of the momentum (in kgm/s) of an electron traveling at 0.8c

Homework Equations


p = mv

The Attempt at a Solution


see photo. I said A but the answers said B.
 

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pkc111 said:

Homework Statement


What is the magnitude of the momentum (in kgm/s) of an electron traveling at 0.8c

Homework Equations


p = mv
p=mv is the classical approximatation accurate only for low speeds.

80% light speed is certainly not a low speed!

What is the relativistic definition of momentum?
 
Thank you!
 
pkc111 said:
What is the magnitude of the momentum (in kgm/s) of an electron traveling at 0.8c
it should be m0v/√(1-v2/c2),
m0 being the rest mass of the electron.
 
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