Question

The weight of a person is 60 kg If he gets $10^{5}$ calories of heat through food and the efficiency of his body is $28 \%,$ then upto how much height he can climb? (Take $\left.g=10\, m\, s ^{-2}\right)$

• A. 100 m
• B. 196 m
• C. 400 m
• D. 1000 m

Answer 1

Answer: (B)

$W=\eta \cdot Q=\left(\frac{28}{100}\right) \cdot\left(10^{5}\right.$ cal $)$
$W=\left(\frac{28}{100} \times 10^{5} \times 4.2\right) J$
But $W=m \cdot g \cdot h$
$h=\frac{W}{m g}=\left(\frac{28 \times 10^{5} \times 4.2}{100 \times 60 \times 10}\right)=196 m$.