Assertion : For the planets orbiting around the sun, angular spee… - Vidyadip

Question

Assertion : For the planets orbiting around the sun, angular speed, linear speed, K.E. changes with time, but angular momentum remains constant.
Reason : No torque is acting on the rotating planet. So its angular momentum is constant.

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Answer

(a) The torque on a body is given by $\vec{\tau}=\frac{d \vec{L}}{d t}$In case of planet orbiting around sun no torque is acting on it. $\frac{d \vec{L}}{d t}=0 \Rightarrow \vec{L}=$ constant.

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