Suppose an object whose mass is m is moving with a speed of 0.8c.Which is the correct expression for its kinetic energy? A)K = mv²/2 B)K = γmc² C)K = (γ − 1)mc² D)Answers a and c are both correct.

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Quizplus · Accepted Answer

The expression for relativistic kinetic energy is K = (γ - 1)mc^2, where γ is the Lorentz factor given by γ = 1/√(1 - v^2/c^2) with v being the velocity of the object and c being the speed of light. Plugging in the given values, we get K = (γ - 1)mc^2 = (1/√(1 - 0.8^2) - 1)mc^2 = 2.24mc^2. Option A is incorrect as it has a wrong formula for kinetic energy, while options B and D give the correct formula but with incorrect numbers.

Suppose an Object Whose Mass Is M Is Moving with a Speed