Find the speed of an electron given momentum

[psilovethomas]

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?

 

[kuruman]

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.