The figure shows elliptical orbit of a planet 'M' about the Sun 'S', the shaded area SCD is twice the shaded area SAB. If `t_(1)` is the time for the planet to move from C and D and `t_(2)` is the time to move from A to B then.

Explanation

According to Kepler.s law
Law of areas
`(DeltaA)/(Deltat) ` = constant
`DeltaA prop Deltat`
`(DeltaA_(SCD))/(DeltaA_(SAB)) = (t_(1))/(t_(2))`
`(2A)/A = (t_(1))/(t_(2))`
` :. " " t_(1) = 2t_(2)`