The figure shows elliptical orbit of a planet m about the

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The figure shows elliptical orbit of a planet m about the sun S. The shaded area SCD is twice the shaded area SAB. If t₁ is the time for the planet to move from C to D and t₂ is the time to move from A to B then :

1. t₁ = 4t₂
2. t₁ = 2t₂
3. t₁ = t₂
4. t₁ > t₂

Correct Option: B

According to Kepler’s law, the areal velocity of a planet around the sun always remains constant.
SCD : A₁ – t₁ (areal velocity constant)
SAB : A₂ – t₂

	A₁	=	A₂
	t₁		t₂

t₁ = t₂.	A₁	(given A₁ = 2A₂)
	A₂

= t₂.	2A₂
	A₂

∴ t₁ = 2t₂