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Exercises Relativity, quantum and nuclear

Quick check from College Physics, 28.5 Relativistic Momentum

Relativistic Momentum: quick check

What is the momentum of an electron traveling at a speed $0.985 c$ ? The rest mass of the electron is $9 . 11 \times 10^{- 31} kg$ .

Answer it in your own words before you look.

Answer
$p = γ mu = \frac{mu}{\sqrt{1 - \frac{u^{2}}{c^{2}}}} = \frac{(9 . 11 \times 10^{- 31} kg) (0.985) (3.00 \times 10^{8} m/s)}{\sqrt{1 - \frac{(0.985 c)^{2}}{c^{2}}}} = 1.56 \times 10^{- 21} kg \cdot m/s$
28.42

How did it go?

PreviousRelativistic Addition of Velocities: quick check Next Calculating Rest Energy: Rest Energy is Very Large

From College Physics (1st edition) by OpenStax (Rice University), section 28.5, licensed under CC BY 4.0. Original at openstax.org. We split the solution into steps; the words, numbers and figures are the book's. OpenStax doesn't endorse this site.