A kg person stands in a lift accelerating upwards at m/s. Taking m/s, what is the reaction force from the floor?
Answer and explanation
Correct answer: A. 791 N
- Step 1: Newton's second law upwards: . Step 2. N. Answer: 791 N. Why not the others: 686 N is the stationary reading (); 581 N would apply if the lift were accelerating downwards; 105 N is only the extra force needed for acceleration.
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