Question

An electric motor driven piston pump that gives 2 hp output has overall efficiency of 89%. What is the input given to the electric motor its overall efficiency is 75%.

Answer 1

Input to the electric motor=2.99 hp.

Step-by-step explanation:

Given

Out put from pump=2 hp

`We\ know\ that\ efficiency\ \eta =(out\ put)/(in\ put)`

To find input to the pump

`\eta =(out\ put)/(in\ put)`

⇒
`0.89=(2)/(in\ put)`

So in put=2.24 hp.

Now to find electric motor in put

`0.75 =(2.24)/(in\ put)`

So input to the electric motor=2.99 hp.