A man in lift reads W 1 when going up with acceleration a, and W 2 when going down with same acceleration a. His true weight is:

⚛️ Physics · Laws of Motion · NEET & JEE

A man in lift reads W₁ when going up with acceleration a, and W₂ when going down with same acceleration a. His true weight is:

Answer: (W₁ + W₂)/2.

A W₁ + W₂
B (W₁ + W₂)/2
C W₁ - W₂
D (W₁ - W₂)/2

Correct answer: B. (W₁ + W₂)/2

Explanation: W₁ = m(g+a), W₂ = m(g-a). Adding: W₁+W₂ = 2mg. True weight = mg = (W₁+W₂)/2.

Free-body diagram of a block on an incline: weight (mg) resolves into mg sinθ along the slope and mg cosθ into the slope, balanced by the normal force N and friction f.

Concept context

Newton's three laws, friction, circular motion, and free body diagrams.

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A man in lift reads W1 when going up with acceleration a, and W2 when going down with same acceleration a. His true weight is:

Concept context

More Laws of Motion questions

A man in lift reads W₁ when going up with acceleration a, and W₂ when going down with same acceleration a. His true weight is: