A pulley system is marked with a mechanical advantage of 2.5. A worker applies 450N to the pulley in an attempt to sound system with a 1500N weight. Of this task we could say that:
A It is impossible to lift that much weight with this system so no movement should be observed.
BIt is impossible to lift the sound system using a pulley system, you must use a third-class lever.
The work done by the worker will be lower than the work done by the pulley system while lifting the sound system
The mechanical advantage must be incorrect, as the mechanical advantage can not have decimals.
The correct answer is:
The work done by the worker will be lower than the work done by the pulley system while lifting the sound system.
Since the mechanical advantage is 2.5, the worker applies 450N of force. This means that the pulley system will exert a force of (2.5)(450N) = 1125N. Since the weight of the sound system is 1500N, the force exerted by the pulley system is lower than the weight of the sound system. Hence, the work done by the worker will be lower than the work done by the pulley system while lifting the sound system.