Physics · 2025
JEE Main · 29 January 2025, Shift 2 · Q30
A cup of coffee cools from 90^° C to 80^° C in t minutes when the room temperature is 20^° C. The time taken by the similar cup of coffee to cool…
A cup of coffee cools from $\displaystyle 90^{\circ} \mathrm{C}$ to $\displaystyle 80^{\circ} \mathrm{C}$ in t minutes when the room temperature is $\displaystyle 20^{\circ} \mathrm{C}$. The time taken by the similar cup of coffee to cool from $\displaystyle 80^{\circ} \mathrm{C}$ to $\displaystyle 60^{\circ} \mathrm{C}$ at the same room temperature is :
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle \frac{13}{5} t$
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.