Which expression gives kinetic energy?

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Multiple Choice

Which expression gives kinetic energy?

Kinetic energy depends on motion, increasing with mass and with the square of speed. The standard expression for it is Ek = 1/2 m v^2, which shows that energy grows rapidly as velocity grows and that mass adds linearly. This form also explains why doubling the speed makes kinetic energy four times larger, and doubling the mass doubles the energy. The other expressions describe different ideas: Egrav = mgh is energy due to height in a gravitational field; W = Fd is the general work done by a force over a distance (energy transfer, not a specific kinetic-energy form); Ek = m v^2 is missing the crucial 1/2 factor, so it doesn’t match the true kinetic-energy formula. Therefore the correct expression for kinetic energy is Ek = 1/2 m v^2.

Kinetic energy depends on motion, increasing with mass and with the square of speed. The standard expression for it is Ek = 1/2 m v^2, which shows that energy grows rapidly as velocity grows and that mass adds linearly. This form also explains why doubling the speed makes kinetic energy four times larger, and doubling the mass doubles the energy.

The other expressions describe different ideas: Egrav = mgh is energy due to height in a gravitational field; W = Fd is the general work done by a force over a distance (energy transfer, not a specific kinetic-energy form); Ek = m v^2 is missing the crucial 1/2 factor, so it doesn’t match the true kinetic-energy formula. Therefore the correct expression for kinetic energy is Ek = 1/2 m v^2.

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