MCQ
If earth suddenly stops rotating about its own axis, the increase in it’s temperature will be
- ✓$\frac{{{R^2}{\omega ^2}}}{{5Js}}$
- B$\frac{{{R^2}{\omega ^2}}}{{Js}}$
- C$\frac{{Rm{\omega ^2}}}{{5Js}}$
- DNone of these
✓
Answer
Correct option: A.
$\frac{{{R^2}{\omega ^2}}}{{5Js}}$
a
(a) $W = JQ \Rightarrow \frac{1}{2}I{\omega ^2} = J(MS\Delta \theta ) \Rightarrow \frac{1}{2}\left( {\frac{2}{5}M{R^2}} \right)\,{\omega ^2}$
(a) $W = JQ \Rightarrow \frac{1}{2}I{\omega ^2} = J(MS\Delta \theta ) \Rightarrow \frac{1}{2}\left( {\frac{2}{5}M{R^2}} \right)\,{\omega ^2}$
$ = J(MS\Delta \theta ) \Rightarrow \Delta \theta = \frac{{{R^2}{\omega ^2}}}{{5Js}}$
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