Question:medium
If the kinetic energy of a body moving with a velocity of $(2\vec{i}+3\vec{j}-4\vec{k})$ ms$^{-1}$ is 87 J, then the mass of the body is
If the kinetic energy of a body moving with a velocity of $(2\vec{i}+3\vec{j}-4\vec{k})$ ms$^{-1}$ is 87 J, then the mass of the body is
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Kinetic energy is a scalar quantity that depends on the speed (magnitude of velocity), not the velocity vector itself. To find the kinetic energy from a velocity vector, you must first calculate the square of its magnitude: $v^2 = v_x^2 + v_y^2 + v_z^2$.
Updated On: Mar 30, 2026
- 3 kg
- 12 kg
- 9 kg
- 6 kg
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The Correct Option is D
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