Question

Boiling water at ${100}^{0}C$ and cold water at $t^{0}C$ are mixed in the ratio $1:3$ and the resultant maximum temperature was ${27}^0$C. Assuming no heat losses, the value of t is :

• A. $4^{0}C$
• B. ${9.33}^{0}C$
• C. ${2.67}^{0}C$
• D. ${6.67}^{0}C$

Answer 1

The correct option is C ${2.67}^{0}C$

Heat lost by hot water $=$ Heat gained by cold water

$m_h.c.\Delta T_1=m_c.c.\Delta T_2$

$\frac{m_h}{m_c}=\frac{27-t}{100-27}$

$\frac{1}{3}=\frac{27-t}{73}$

$81-3t=73$

$t={2.67}^{0}C$