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Modern Physics

Olympiad (NSEP) level, single correct, hard

3 of 5

Question 3 of 5

A particle of rest mass $m_0$ moves with speed $v = 0.8c$ . The relativistic kinetic energy of the particle is equal to:

Show answer and solution

Answer: (B) $\frac{2}{3} m_0 c^2$

\gamma = \frac{1}{\sqrt{1 - v^2/c^2}} = \frac{1}{\sqrt{1 - 0.64}} = \frac{1}{0.6} = \frac{5}{3}

. Kinetic energy

K = (\gamma - 1) m_0 c^2 = (5/3 - 1) m_0 c^2 = \frac{2}{3} m_0 c^2

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Olympiad (NSEP) Physics practice question on Modern Physics, with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.

A particle of rest mass m0m_0m0​ moves with speed v=0.8cv = 0.8cv=0.8c. The relativistic kinetic energy of the particle is equal to:

More Physics practice

A particle of rest mass $m_0$ moves with speed $v = 0.8c$ . The relativistic kinetic energy of the particle is equal to: