Answer:
1. The input power is 17.6 Watts
2. The output power is 0.7232 Watts
3.The efficiency of the hand crank generator is approximately 4.109%
Explanation:
The given parameters are;
The force with which the crank generator is turned = 22 Newtons
The rate at which the crank is turned = 8 revolutions per 3 seconds
The distance the hand moves during each revolution = 0.3 meters
The current recorded by the multimeter = 0.08 amps
The voltage recorded by the multimeter = 9.04 volts
1. Power = The rate of doing work = Work done/(Time taken to do the work) = Force × Distance/Time
∴ The power input of the hand crank generator = 22 × 0.3 × 8/3 = 17.6 Watts
2. The power output to the bulb, P, is given by the formula for electrical power as follows;
Power = Current, I × Voltage V
∴ P = 0.08 × 9.04 = 0.7232 Watts
3. Efficiency in percentage = Output/Input × 100
Therefore, the efficiency of the hand crank generator = )Output power/(Input power)) × 100 = (0.7232/17.6) × 100 ≈ 4.109%
