Calculadora de Potência de Ciclismo — Formula
## How Cycling Power Is Estimated
Power required to cycle comes from three main sources: aerodynamic drag, rolling resistance, and gravity.
### Formula
**Total Power = P_aero + P_rolling + P_gravity**
- **P_aero = 0.5 x air density x CdA x v^3** (CdA assumed 0.32 x 0.88)
- **P_rolling = Crr x mass x g x v** (Crr assumed 0.005)
- **P_gravity = mass x g x gradient x v**
Where v is speed in m/s, g is 9.81 m/s^2.
### Key Insight
Aerodynamic drag increases with the cube of speed, so doubling your speed requires roughly 8 times the power to overcome air resistance.
Power required to cycle comes from three main sources: aerodynamic drag, rolling resistance, and gravity.
### Formula
**Total Power = P_aero + P_rolling + P_gravity**
- **P_aero = 0.5 x air density x CdA x v^3** (CdA assumed 0.32 x 0.88)
- **P_rolling = Crr x mass x g x v** (Crr assumed 0.005)
- **P_gravity = mass x g x gradient x v**
Where v is speed in m/s, g is 9.81 m/s^2.
### Key Insight
Aerodynamic drag increases with the cube of speed, so doubling your speed requires roughly 8 times the power to overcome air resistance.
Exemplo Resolvido
Riding at 18 mph on flat road, 185 lbs total rider+bike weight.
- Speed = 18 * 0.44704 = 8.05 m/s
- Mass = 185 * 0.4536 = 83.9 kg
- P_aero = 0.5 * 1.225 * 0.2816 * 8.05^3 = 90.0 W
- P_rolling = 0.005 * 83.9 * 9.81 * 8.05 = 33.1 W
- P_gravity = 0 (flat road)
- Total = 90 + 33 + 0 = 123 W
- W/kg = 123 / 83.9 = 1.47 W/kg