Kepler's second law of motion states that the straight line joining the planet to sun sweeps out equal areas in equal intervals of time. This statement is equivalent to saying that

Options

A. longitudinal acceleration is zero
B. total acceleration is zero
C. radius acceleration is zero
D. tangential acceleration is zero

Answer

D

Explanation

The areal velocity of a planet remains constant and `(Delta A)/(Delta t) = (1)/(2)(L)/(m) =` constant
where L is its angular momentum.
Kepler's second law is a consequence of the principle of conservation of angular momentum.
`because` L is constant `" " therefore tau = (dL)/(dt)=0`
But `tau = I alpha = 0 " " therefore alpha = 0(because 1 ne 0)`
`therefore` Tangential acceleration `a_(T)=r alpha =0`