Question

What is power of the pump which takes 10 seconds to lift 100kg of water to a water tank?

Answer 1

Given, Mass of the water= 100kg

Time taken=10secs

W= mg

= 100 x 9.8

= 980N

We know, P= W/t

= 980/10

= 98N/s

= 98 W

Answer 2

$\huge\star\sf\underline\pink{Solution:-}$

We have,

$\sf{Mass\:of\: water (m) = 100kg} \\ \\ \sf{Acceleration\:due\:to\: gravity (g) = 10\:ms^{-2}} \\ \\ \sf{Height (h) = 20\:m} \\ \\ \\ \sf\underline\red{To\:Find:-} \\ \\ \: \: \: \: \bullet\sf{Power =?} \\ \\ \\ \sf\underline\red{Formula:-} \\ \\ \blue{\boxed{\sf{ w = m \times g \times h }}}$

Now,

By putting Values in the Formula,

We get:

$\sf{ Work\: Done = 100 \times 10 \times 20} \\ \\ \\ \longrightarrow\sf{ 20000\:J} \\ \\ \sf{Time\:Taken(t) = 10s}$

We know that,

$\huge\green{\boxed{\sf{ Power (p) = \dfrac{W}{t} }}} \\ \\ \\ \longrightarrow\sf{ \dfrac{20000}{10} } \\ \\ \\ \longrightarrow\sf{ 2000 \:Watts \: \: (2000\:W) }$

Thus,

The Power this pump is 2000 Watts.

We have to convert this watts power into kilowatt by dividing it by 1000.

So,

$\longrightarrow{\boxed{\sf{ Power = \dfrac{2000}{1000} }}} \\ \\ \\ \longrightarrow\sf{ 2 \: kilowatts }$