Physics · 2021
JEE Main · 26 February 2021, Shift 1 · Q6
A large number of water drops, each of radius r, combine to have a drop of radius R. If the surface tension is T and mechanical equivalent of heat is…
A large number of water drops, each of radius r , combine to have a drop of radius R . If the surface tension is T and mechanical equivalent of heat is J, the rise in heat energy per unit volume will be :
Official answer
(2)
$\displaystyle \frac{3 \mathrm{~T}}{\mathrm{~J}}\left(\frac{1}{\mathrm{r}}-\frac{1}{\mathrm{R}}\right)$
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JEE Main 2021 Physics question, with the answer from NTA’s final answer key. Where our answers come from.