Find the speed of an electron given momentum

AI Thread Summary
To find the speed of an electron given its momentum of 2.74 x 10^-22 kg·m/s, the correct approach involves using the equation p = γmv, where γ (gamma) accounts for relativistic effects. The initial attempt to calculate speed using v = p/m is incorrect because it does not consider the relativistic factor. Instead, the speed should be calculated using v = p/(γm), requiring the expression for γ to be defined in terms of v. This leads to a more complex equation that must be solved iteratively or through substitution. Understanding the relationship between momentum, mass, and relativistic speed is crucial for accurate calculations.
psilovethomas
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Homework Statement


An electron has momentum of magnitude 2.74 10-22 kg · m/s. What is the electron's speed?

Homework Equations


p=ymv, where y=gamma


The Attempt at a Solution


v=p/m, which is wrong. Any suggestions?
 
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psilovethomas said:

Homework Statement


An electron has momentum of magnitude 2.74 10-22 kg · m/s. What is the electron's speed?

Homework Equations


p=ymv, where y=gamma


The Attempt at a Solution


v=p/m, which is wrong. Any suggestions?
If p = γmv, then v = p/γm not p/m. Of course, γ itself is a function of v, so you need to write it out and then solve for v correctly.
 

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