Question

A painter needs to buy a new pulley system. Both systems have an input work of 100 J, but the old system model has an output work of 60 J and the new system model has an output work of 75 J.

Which system is more efficient?

Answer 1

The new pulley system with 75% efficiency is more efficient than the old one with 60% efficiency because it has a higher ratio of output work to input work.

Step-by-step explanation:

It has been asked that which of two pulley systems is more efficient. Efficiency is calculated as the ratio of output work to input work, expressed as a percentage. For the old system, the efficiency can be calculated as (60 J / 100 J) × 100%, which is 60%. For the new system, the efficiency is (75 J / 100 J) × 100%, amounting to 75%. Therefore, the new system, with 75% efficiency, is more efficient than the old system that has only 60% efficiency.

If you were to calculate the efficiency of a pulley system, one additional piece of information you would need is the weight of the load being lifted. This, along with the input force and the distances moved by the input and the load, help to determine the mechanical advantage and work done by the system.

Answer 2

The answer is the old model is better