Question

A rocket is fired vertically up from the ground. It
moves with a constant acceleration 15 ms-2 for
30 seconds. After 30 seconds, fuel tank becomes
empty. Due to inertia, the rocket continues to move
up under the action of gravity. The total time taken
by the rocket from the instant of firing to attain the
maximum height is (g
g=10ms)
1) 60 s
2) 75 s
3) 90 s
4) 120 S​

Answer 1

pls refer the attachment

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