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

[pkc111]

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.

 

[Hiero]

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?

 

[pkc111]

Thank you!

 

[Apashanka]

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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