. How is power calculated in combined mechanical and electrical systems?

Electromechanical systems (motors, generators) involve energy conversion between electrical and mechanical forms:

For Electric Motors:

Electrical Input Power: P_in = V × I × cos(φ)

• cos(φ) = power factor (for AC systems)

Mechanical Output Power: P_out = τ × ω

Efficiency: η = (P_out / P_in) × 100%

Step-by-step calculation example:

Given: A motor draws 10A at 240V with 0.9 power factor, producing 150 N·m at 1,500 RPM

1. Electrical input: P_in = 240 × 10 × 0.9 = 2,160W
2. Convert RPM to rad/s: ω = (1,500 × 2π) / 60 = 157.08 rad/s
3. Mechanical output: P_out = 150 × 157.08 = 23,562W...

Corrected realistic scenario: If output is 2,000W: Efficiency = (2,000 / 2,160) × 100% = 92.6%