Question

A machine performs 1820 J of work in 20 seconds. The power of the machine is

a 90 W
b 91 W
c 92 W
d 93 W
​

Answer 1

Given :-

Work done by the machine = 1820 J

Time taken by the machine to perform the work = 20 sec

To Find :-

The power of the machine.

Analysis :-

Here we are given with the work done and the time taken by the machine.

In order to find the power of the machine, substitute the values given in the questions accordingly such that power is equal to the work done divided by the time taken by the machine.

Solution :-

We know that,

• w = Work done
• p = Power
• t = Time

Using the formula,

$\underline{\boxed{\sf Power = \dfrac{Work \ done}{Time \ taken} }}$

Given that,

Work done (w) = 1820 J

Time taken (t) = 20 sec

Substituting their values,

⇒ p = w/t

⇒ p = 1820/20

⇒ p = 91 W

Therefore, the power of the machine is 91 W.

Answer 2

Answer:

Given :-

Work done by the machine = 1820 J

Time taken by the machine to perform the work = 20 sec

To Find :-

The power of the machine.

Solution :-

$\huge \boxed { \bf \: P= \frac{W}{T} }$

Here,

P = Power

W = Work

T = Time

$\sf \: p \: = \dfrac{1820}{20}$

$\sf \: p \: = 91 \: w$

Hence :-

Correct Option (B) = 91 Watt