Question

When 20. joules of work are done in 4.0 seconds; what is the power developed?

A. 0.20 watt

B. 5.0 watts

C. 16 watts

D. 80. watts

Answer 1

`\bold\blue{Formula : }`

`\bold{Power = (energy)/(time) }`

`\bold\blue{Given : }`

• Joules of work = 20

• work are done = 4.0 seconds

`\bold\blue{ Solution : }`

`\bold{Power = (energy)/(time) }`

`\bold{Power = (20)/(4.0) }`

`\bold{ Power = 5.0}`

So , B.) 5.0 watts is answer .

Answer 2

to find:

the power developed when, 20 joules of work are done in 4.0 second.

solution:

power= workdone/ time

here workdone= 20 joules

time taken= 4.0s

so putting these values in the above formula, we get:

power= 20/4.0

=5.0 watts

answer= option b) 5.0 watts