Kinetic Energy Explained

The Formula

KE = ½ × m × v². Kinetic energy depends on velocity squared — doubling the speed multiplies KE by four. This is why vehicle crash safety improves dramatically at lower speeds.

Real-World Examples

A 70kg person walking at 1.4 m/s: KE = 68.6J. Same person running at 4 m/s: KE = 560J. A 1,500kg car at 30 km/h (8.33 m/s): KE = 52,000J. At 60 km/h: KE = 208,000J — four times greater.

Energy Conversion

Kinetic energy is converted to other forms on stopping: to heat (brakes, tyres), sound, and deformation. In regenerative braking systems (hybrid and electric vehicles), KE is converted back to electrical energy.

Kinetic Energy Calculator

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