Q. 125.0( 1 Vote )
Figure (11-Q2) 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.
A. t1 < t2.
B. t1 = t2.
C. t1 > t2.
D. Insufficient information to deduce the relation between t1 and t2.
From Kepler’s second law we know that a planet on a closed orbit sweeps equal areas in equal time. Hence, if the areas are equal, the time taken while traversing the arc enclosing the area will also be equal. Therefore, t1 = t2.
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