Question

A weight lifter lifts a dumbbell a certain height in 2.0 s, while a competitor does the same workin 1.0 s. Compared to the power developed by the first weightlifter, the power developed by thesecond is?
a. one-half as great b. twice as great c. the same d. 4 times as great

Answer 1

Answer:

a. one-half as great

Explanation:

The power developed by the first lifter is one-half as great as that of the second person.

  Power is defined as the rate at which work is done;

          Power  = $\frac{workdone}{time}$

Since the two lifters do the same work at different time, let us estimate their power;

       P₁ = $\frac{workdone}{2}$                     P₂ = $\frac{workdone }{1}$

   We see that for P₁, power is half of the work done whereas in P₂ power is the same as the work done.

Therefore,

           The power of the first weight lifter is one-half the second lifter.