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NTA Abhyas JEE Main2020PhysicsMotion in One DimensionPractice

A lift ascends with constant acceleration a = 1 m s - 2 , then with constant velocity and finally, it stops under constant retardation a = 1 m s - 2 . If total distance ascended by the lift is 7 m , in a total time of the journey is 8 s . Find the time (in second) for which lift moves with constant velocity.

Correct answer

6

Step-by-step solution

a = v t 1 t 1 = v a ...(i) t 0 = 8 - 2 t 1 ...(ii) s 0 = 7 - 2 s 1 ...(iii) Solving equation (i), (ii) and (iii), we get t 0 = 6   s

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