A 4 kg mass hangs from a spring scale in an elevator. Spring reads 32 N. The elevator is:
AAt rest
BAccelerating upward at 2 m/s²
CAccelerating downward at 2 m/s²
DFree falling
Answer & Solution
Correct answer: C. Accelerating downward at 2 m/s²
Weight = 4 × 10 = 40 N. Reading = 32 N (apparent weight). Net force = 40 - 32 = 8 N downward. Acceleration = 8/4 = 2 m/s² downward. The elevator descends (or decelerates while ascending) at 2 m/s².
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