Browse Questions

# An engine develops 10 KW of power How much time will it take to lift mass of 200 kg to a height of 40 m

$(a)\;4\;s \quad (b)\;5\;s \quad (c)\;10\;s \quad (d)\;8\;s$

$P=\large\frac{mgh}{t}$
$=>\large\frac{mgh}{P}$
Therefore $t=\large\frac{200 \times 40 \times 10}{10 \times 10^3}$
$\qquad=8\; seconds$
Hence d is the correct answer.

edited Feb 10, 2014 by meena.p