# When $100 \mathrm{~g}$ of a liquid $\mathrm{A}$ at $100^{\circ} \mathrm{C}$ is added to $50 \mathrm{~g}$ of a liquid $\mathrm{B}$ at temperature $75^{\circ} \mathrm{C}$, the temperature of the mixture becomes $90^{\circ} \mathrm{C}$. The temperature of the mixture, if $100 \mathrm{~g}$ of liquid $\mathrm{A}$ at $100^{\circ} \mathrm{C}$ is added to $50 \mathrm{~g}$ of liquid $\mathrm{B}$ at $50^{\circ} \mathrm{C}$, will be :

Question:

When $100 \mathrm{~g}$ of a liquid $\mathrm{A}$ at $100^{\circ} \mathrm{C}$ is added to $50 \mathrm{~g}$ of a liquid $\mathrm{B}$ at temperature $75^{\circ} \mathrm{C}$, the temperature of the mixture becomes $90^{\circ} \mathrm{C}$. The temperature of the mixture, if $100 \mathrm{~g}$ of liquid $\mathrm{A}$ at $100^{\circ} \mathrm{C}$ is added to $50 \mathrm{~g}$ of liquid $\mathrm{B}$ at $50^{\circ} \mathrm{C}$, will be :

1. $85^{\circ} \mathrm{C}$

2. $60^{\circ} \mathrm{C}$

3. $80^{\circ} \mathrm{C}$

4. $70^{\circ} \mathrm{C}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics Termal Properties of Matter chapter.

JEE Main Previous Year 11 Jan. 2019 II

Correct Option: 3

Solution:

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