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Question
In the Following figure shows the elliptical path of a planet about the sun. The two shaded parts have equal area. If t1 and t2 be the time taken by the planet to go from a to b and from c to d respectively,
Options
t1 < t2
t1 = t2
t1 > t2
insufficient information to deduce the relation between t1 and t2
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Solution
t1 = t2
Kepler's second law states that the line joining a planet to the Sun sweeps out equal areas in equal intervals of time, i.e., areal velocity of a planet about the Sun is constant.
The given areas swept by the planet are equal, so t1 = t2
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