JEE Mains · Physics · STD 11 - 10.1, thermonetry,thermal expansion and calorimetry
- JEE Mains 2019
- Medium
- Numerical
Ice at \(-20\,^oC\) is added to \(50\,g\) of water at \(40\,^oC.\) When the temperature of the mixture reaches \(0\,^oC,\) it is found that \(20\,g\) of ice is still unmelted. The amount of ice added to the water was close to ........\(g\) (Specific heat of water \(= 4.2\,J/g/^oC)\) Heat of fusion of water at \(0^oC = 334\,J/g\) )
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(40\)
Step-by-step Solution
Detailed explanation
\(m \times 0.5 \times 20 + \left( {m - 20} \right) \times 80\)
\( = 50 \times 1 \times 40\)
\( \Rightarrow 90\,m - 1600 = 2000\)
\( \Rightarrow 90\,m = 3600\)
\( \Rightarrow m = 40\,gm\)
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