A rain drop starts falling from a height of `2km`. If falls with a continuously decreasing acceleration and attains its terminal velocity at a height of `1km`. The ratio of the work done by the gravitational force in the first halt to that in the second half of the drops journey isA. `1:1` and the times of fall of the drop in the two haves is `a:1` (where `agt1`)B. `1:1` and the times of fall of the drop in the two halves is `a:1` (where `alt1`)C. `a:1` (where `agt1`) and the times of fall of the drop is the two halves is `1:1`D. `a:1` (where `alt1`) and the times of fall of the drop in the two halves is `1:1`

A rain drop starts falling from a height of `2km`. If falls with a con

1.	A rain drop starts falling from a height of `2km`. If falls with a continuously decreasing acceleration and attains its terminal velocity at a height of `1km`. The ratio of the work done by the gravitational force in the first halt to that in the second half of the drops journey isA. `1:1` and the times of fall of the drop in the two haves is `a:1` (where `agt1`)B. `1:1` and the times of fall of the drop in the two halves is `a:1` (where `alt1`)C. `a:1` (where `agt1`) and the times of fall of the drop is the two halves is `1:1`D. `a:1` (where `alt1`) and the times of fall of the drop in the two halves is `1:1`
Answer» Correct Answer - A Taking `g` constant, work done in both the cases is `-mgxx(1000)` since the maximum velocity of the journey is attained at a height of `1km`, and the second half journey is travelled by max. velocity the time taken for second half journey will be less.

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