Question

An electric motor creates a tension of $4500N$ in a hoisting cable and reels it in at the rate of $2m/s$. What is the power of the electric motor-

Answer 1

Power

1. Power is the work done by a body in unit time.
2. Power is defined by the form, $P=\frac{W}{t}$, where, w is the work done in time t.
3. Power is defined by another form, $P=F.V$ where, F is the force exerted on the body and v is the velocity of the body.

Step 1: Given data

1. The tension due to the electric motor is $F=4500N.$
2. The velocity of the cable is $v=2m/s.$

Step 2: Power of the electric motor

As we know, power, $P=F.V$

So, $$\begin{gathered} P=F.V \\ P=4500\times 2 \\ P=9000watt. \end{gathered}$$

Therefore, the power of the electric motor is $9000watt.$