Question

A juggler throws continuously balls at the rate of three in each second each with a velocity of $10m{s}^{-1}$. If the mass of each ball is $0.05kg$ his power is:

• A. $2W$
• B. $50W$
• C. $0.5W$
• D. $7.5W$

Answer 1

The correct option is D $7.5W$

$Power=F.V$

$=\frac{\Delta KE}{t}$

$=\frac{3\times \frac{1}{2}\times m{v}^2}{1}$

$=3\times \frac{1}{2}\times 0.05\times 100=7.5W$