Sign in
Please select an account to continue using cracku.in
↓ →
Join Our JEE Preparation Group
Prep with like-minded aspirants; Get access to free daily tests and study material.
In two glasses there is liquid material of the same type, the volume of one is $$V_1$$, its temperature is $$T_1$$, the volume of the other is $$V_2$$ and its temperature is $$T_2$$. We mix the liquids and wait while the temperature settles. What is the common temperature if we neglect any heat losses? What would be the common temperature if the volume of first liquid is halved and the second liquid doubled.
Correct Answer: 0
The liquids are identical, so mass is proportional to volume and the specific heat cancels. Heat lost by the hotter liquid equals heat gained by the colder one, $$V_1(T_1 - T) = V_2(T - T_2)$$, giving $$T = \frac{V_1T_1 + V_2T_2}{V_1 + V_2}$$. With volumes $$\frac{V_1}{2}$$ and $$2V_2$$ the same rule gives $$T' = \frac{\frac{V_1}{2}T_1 + 2V_2T_2}{\frac{V_1}{2} + 2V_2} = \frac{V_1T_1 + 4V_2T_2}{V_1 + 4V_2}$$.
Was this solution helpful?
Predict your JEE Main percentile, rank & performance in seconds
Educational materials for JEE preparation