A girl whose mass is 55kg stands on a spring - weighing machine inside a lift. When the lift starts to ascend, its acceleration is 2ms1. What will be the reading on the machine? (Take g = ms-2)
A
66 kg
B
55 kg
C
44 kg
D
22 kg
Correct Answer:
A
Reading = mg + ma = m(g + a) = 55(10 + 2)
= 660N = 66kg