JEE Mains · Physics · STD 11 - 10.2 transmission of heat
A hot body, obeying Newton's law of cooling is cooling down from its peak value \(80\,^oC\) to an ambient temperature of \(30\,^oC\) . It takes \(5\, minutes\) in cooling down from \(80\,^oC\) to \(40\,^oC\). ........ \(\min.\) will it take to cool down from \(62\,^oC\) to \(32\,^oC\) ? (Given \(ln\, 2\, = 0.693, ln\, 5\, = 1.609\))
- A \(3.75\)
- B \(8.6\)
- C \(9.6\)
- D \(6.5\)
Answer & Solution
Correct Answer
(B) \(8.6\)
Step-by-step Solution
Detailed explanation
From \(Newton's\,law\) of cooling, \(t = \frac{1}{k}{\log _e}\left( {\frac{{{\theta _2} - {\theta _0}}}{{{\theta _1} - {\theta _0}}}} \right)\) From question and above equation,…
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