5.13 A man of mass 70 kg stands on a weighing scale in a lift which is moving

(a) Upwards with a uniform speed of 10 m s^-1

 

(b) Downwards with a uniform acceleration of 5 m s^-2

 

(c) Upwards with a uniform acceleration of 5 m s^-2. What would be the readings on the scale in each case?

 

(d) What would be the reading if the lift mechanism failed and it hurtled down freely under gravity?

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