Question 701: Centre of Mass and Rotational Motion

Question

If the rotational kinetic energy of a body is increased by $300 \%$, then the percentage increase in its angular momentum will be

Accepted Answer

$$ \begin{aligned} \because E_{k r} & =\frac{J^2}{2 I} \ J & =\sqrt{2 I E_{k r}} \end{aligned} $$
Percentage increase in J .
$$ \begin{gathered} \left(\frac{J_2-J_1}{J_1} 	imes 100ight)=\frac{\sqrt{E_{k r_2}}-\sqrt{E_{k r_1}}}{\sqrt{E_{k r_1}}} 	imes 100 \ =\frac{\sqrt{400}-\sqrt{100}}{\sqrt{100}} 	imes 100 \ =\frac{20-10}{10} 	imes 100=100 \% \end{gathered} $$

Answer

$10 \%$

Answer

$100 \%$

Answer

$150 \%$

Answer

$200 \%$

Centre of Mass and Rotational Motion

If the rotational kinetic energy of a body is increased by 300 \%, then the percentage increase in its angular momentum will be

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