What is the formula for kinetic energy?

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Multiple Choice

What is the formula for kinetic energy?

Kinetic energy is the energy an object has because it is moving. It depends on both how heavy it is (mass) and how fast it is going (speed), and it grows with the speed squared, so doubling the speed makes the energy quadruple. The formula is KE = 1/2 m v^2. Here m is mass in kilograms, v is speed in metres per second, and KE is in joules. For example, a 2 kg object moving at 3 m/s has KE = 1/2 × 2 × 3^2 = 9 J. Other expressions describe different ideas: m g h is gravitational potential energy (energy due to height), m c ΔT relates to heat energy (change in temperature with specific heat capacity), and m v^2 would be twice the correct kinetic energy because of the missing 1/2 factor.

Kinetic energy is the energy an object has because it is moving. It depends on both how heavy it is (mass) and how fast it is going (speed), and it grows with the speed squared, so doubling the speed makes the energy quadruple.

The formula is KE = 1/2 m v^2. Here m is mass in kilograms, v is speed in metres per second, and KE is in joules. For example, a 2 kg object moving at 3 m/s has KE = 1/2 × 2 × 3^2 = 9 J.

Other expressions describe different ideas: m g h is gravitational potential energy (energy due to height), m c ΔT relates to heat energy (change in temperature with specific heat capacity), and m v^2 would be twice the correct kinetic energy because of the missing 1/2 factor.

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