Question

A candy bar supplies your muscles with energy. If your muscles are 40% efficient, how much work can they perform if the candy contains 800 J?

Answer 1

The muscles can perform 320 J of work.

Step-by-step explanation:

Let the work performed by the muscles be
`W_(out)` J.

Efficiency of a body is given as the ratio of useful work to that of work supplied.

Here, the work provided by the candy bar is,
`W_(in)=800\ J`

Efficiency of the muscles is,
`\eta =40\%=0.40`

Now, we know that,

`\textrm{Efficiency,}\ \eta=(W_(out))/(W_(in))\\0.40=(W_(out))/(800)\\W_(out)=0.40* 800=320\ J`

Therefore, the work performed by the muscles is 320 J.