The figure shows a planet in elliptical orbit around the sun $$S.$$ Where is the kinetic energy of the planet maximum?
A.
$${P_1}$$
B.
$${P_2}$$
C.
$${P_3}$$
D.
$${P_4}$$
Answer :
$${P_4}$$
Solution :
Angular momentum of the planet about $$S$$ is conserved. So, $$mvr = {\text{constant}}{\text{.}}$$
$$v$$ is maximum when $$r$$ is minimum.
So, $$v$$ is maximum at point $${P_4}.$$ Hence $$K.E.$$ is maximum at $${P_4}.$$
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