Question

A step supplies water at 22${}^{o}C$. A man take 1 liter per minute at 37${}^{o}C$ from the geyser. the power of geyser is

• A. 2100 W
• B. 1050 W
• C. 1575 w
• D. 525 W

Answer 1

The correct option is B 1050 W

Given
$T_1={22}^{\circ }$ C $T_2={37}^{\circ }$ C $m=1$ litre $t=1$ min
Heat required by water per second to change its temperature from ${22}^{\circ }$C to ${37}^{\circ }$ C
$\frac{dQ}{dt}=\frac{dm}{dt}C(T_2-T_1)$

$\frac{dQ}{dt}=\frac{1000}{60}\left(1\right)(37-22)$

$\frac{dQ}{dt}=250$ cal s${}^{-1}$

$\frac{dQ}{dt}=250\times 4.2$ Js${}^{-1}$

$\frac{dQ}{dt}=1050$ Js${}^{-1}$