Question

A man weighing $60kg$ climbs up a staircase carrying a load of $20kg$ on his head. The stair case has $20$ steps each of height $0.2m$. If he takes $10s$ to climb, find his power.

• A. $313.6W$
• B. $120.6W$
• C. $510W$
• D. $0$

Answer 1

Answer: (A)

$313.6W$

Here, $m=60+20=80kg$
$h=20\times 0.2=4m,$

$g=9.8m{s}^{-2},$

$t=10s$

Now $power=\frac{energy}{time}$

$P=\frac{W}{t}=\frac{mgh}{t}$

$=\frac{80\times 9.8\times 4}{10}$

$=\frac{3136}{10}=313.6W$.