Question

How efficient is a pulley system if it enables you to lift a 700.0 Newton engine (Fr) 0.550 meters (dr) if you exerted 35.7 Newtons (Fe) of force while pulling 11.43 meters (de) of rope?

Answer 1

The efficiency of the pulley system is 87.4%.

Step-by-step explanation:

The efficiency of a pulley system can be calculated using the formula:

Efficiency = (output work / input work) x 100%

In this case, the input work is the force exerted while pulling the rope (Fe) multiplied by the distance the rope is pulled (de). The output work is the weight of the engine (Fr) multiplied by the distance it is lifted (dr). The equation for efficiency can be written as:

Efficiency = (Fr x dr) / (Fe x de) x 100%

Substituting the given values:

Efficiency = (700.0 N x 0.550 m) / (35.7 N x 11.43 m) x 100% = 87.4%

Therefore, the efficiency of the pulley system is 87.4%.

Answer 2

96.3%

Step-by-step explanation:

Efficiency = Work input/Work output * 100%

Work done = Force * distance\

Work done by the engine is the work output = 700 * 0.55

Work output = 423.5Nm

Work done by you is the work input = 35.7*11.43

Work input = 408.051Nm

Efficiency = 408.051/423.5 * 100

Efficiency = 0.963 * 100

Efficiency = 96.3%

Hence the efficiency of the pulley system is 96.3%