Final answer:
The efficiency of a ramp can be calculated by comparing the work input to the work output. In this case, the work input is the force exerted by the man in moving the washing machine up the ramp, and the work output is the increase in potential energy of the washing machine. The efficiency of the ramp is calculated to be 104%.
Step-by-step explanation:
The efficiency of a ramp can be calculated by comparing the work input to the work output. In this case, the work input is the force exerted by the man in moving the washing machine up the ramp, and the work output is the increase in potential energy of the washing machine. Work is calculated using the formula Work = force * distance. Therefore, the work input is 500 N * (0.8 m), and the work output is 650 N * (0.8 m). The efficiency of the ramp can be calculated by dividing the work output by the work input and multiplying by 100%.
The efficiency = (work output / work input) * 100%
Substituting in the values:
Efficiency = (650 N * 0.8 m) / (500 N * 0.8 m) * 100% = 104%.