Question

A 40 kg boy stands on a spring scale in a lift. At an instant, it is detected that the reading reduces to 30 kg for a while and then returns to original value. It can be said that

• A. The lift was in constant motion $\uparrow$
• B. The lift was in constant motion $\downarrow$
• C. The lift in $\downarrow$ motion suddenly stopped
• D. The lift in $\uparrow$ motion suddenly stopped.

Answer 1

Answer: (C)

During accelerated downward motion the apparent weight becomes m (g - a) i.e. reduced. If the lift stops the apparent weight will become equal to actual weight.