Q2 of 26 Page 13

A lift is coming from 8th floor and is just about to reach 4th floor. Taking ground floor as origin and positive direction upwards for all quantities, which one of the following is correct?

The upward direction is positive, the lift is moving downwards, hence, the displacement and the velocity will be negative. Acceleration is the change of velocity. Since the lift is about to stop, there will be retardation/ negative acceleration in downward direction which is same as positive acceleration in upward direction. Thus, acceleration will be positive.

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