A person standing on a spring balance inside a stationary lift measures 60 kg. The weight of that person if the lift descends with uniform downward acceleration of 1.8 m/s2 will be ______________ N. [g = 10 m/s2]
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Correct Answer: 492
Solution and Explanation
When the lift accelerates downward with a = 1.8 m/s2: \(mg - N = ma\).
\(N = m(g-a) = 60\times(10-1.8) = 60\times 8.2 = 492\) N.
Answer: 492
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