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A man of mass 75kg stands on a weighing machine in a lift. Determine the reading on the weighing
machine when the lift:
a) Ascends with an acceleration of 2m/s5.
F=ma=R-mg
(75*2)=R-(75*2)
R=150+750 =900N
b) Descends at a constant velocity of 1.5m/s.
F=ma=mg-R
c) Descends with an acceleration of 5.5m/s5.
R=750 - 183.5=565.5N
Moraa orina answered the question on April 8, 2018 at 17:41
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