The physics
Kinetic energy is the energy of motion: half the mass times velocity squared. The squared term is the punchline — double your speed and you carry four times the energy, which must all go somewhere when you stop.
Kinetic energy of a 90 kg cyclist and bike at 30 km/h
Answer: kinetic energy = 3,125 J (in kilowatt-hours 0.00087 kWh).
What we know
- Mass: 90 kg
- Velocity: 30 km/h = 8.333333333 m/s (converted to the unit the formula takes)
Step by step
- Given
- m = 90 kg, v = 8.333333333 m/s
- Formula
- KE = ½ × m × v²
- Substitute
- KE = ½ × 90 × 8.333333333²
- Result
- KE = 3,125 J
All results
| Kinetic energy | 3,125 J |
|---|---|
| In kilowatt-hours | 0.00087 kWh |
Open the kinetic energy calculator with these numbers → and change any of them.