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 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 $ln\, 2\, = 0.693, ln\, 5\, = 1.609$)
- [JEE MAIN 2014]
- A
$3.75$
- B
$8.6$
- C
$9.6$
- D
$6.5$
Similar Questions
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- [JEE MAIN 2021]
$Assertion :$ Perspiration from human body helps in cooling the body.
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- [AIIMS 2006]
A calorimeter of mass $0.2$ kg and specific heat $900 J/kg-K$ . Containing $0.5$ kg of a liquid of specific heat $2400J /kg-K$ . Its temperature falls from ${60^o}C\,{\rm{to}}\,\,{\rm{5}}{{\rm{5}}^{\rm{o}}}C$ in one minute. The rate of cooling is ....... $J/s$
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