Question

Water is pumped from a stream at the rate of 90kg every 30s and sprayed

Answer 1

Answer:

The power of the pump is 337.5 W.

Explanation:

Power is the rate of transfer of energy or the rate at which work is done. It is measured in watts (W).

                       Power = $\frac{Energy}{Time}$

But the energy here is the kinetic energy (K.E), which is the energy possessed by a moving body or object.

           K.E = $\frac{1}{2}$ m$v^{2}$

where m is the mass = 90 kg and v is the velocity = 15 m/s.

    K.E =  $\frac{1}{2}$ × 90 × $15^{2}$

         = 10125 Joules

  K.E = 10125 J = 10.125 KJ

So that the power of the pump when t = 30 s is;

              Power = $\frac{10125}{30}$

                         = 337.5 W

The power of the pump is 337.5 W.