How do machines make work easier if they do not decrease the amount of work you need to do?

1 Answer
Apr 13, 2018

Machines decrease power needed to perform work

Explanation:

Machines do not change the work done on an object, but they do decrease the power needed to perform the work.

Work is given by W = DeltaE = Fd
where DeltaE is change in energy, F is a force applied, and d is a parallel distance to the force

Power is defined as work over time, or
P = (DeltaE)/(Deltat)

Machines such as pulleys, inclined planes, or screws perform the same work on a system over a greater amount of time. We can see in the power equation that as Deltat increases, power required decreases. This is where the usefulness of machines comes in, they reduce the power needed to perform work.