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A person of mass 50 kg is standing in a lift. If the lift moves in upward direction with an acceleration of 1 m/s2, then the weight of the person will be closest to :
Explanation
The weight of a person in a lift is the normal force exerted by the lift floor on the person, also known as the apparent weight. According to Newton's second law of motion, when a lift moves upward with an acceleration a, the net force equation is:
R - mg = ma
Where:
- R is the apparent weight (normal reaction).
- m is the mass of the person (50 kg).
- g is the acceleration due to gravity (approximately 9.8 m/s2).
- a is the upward acceleration of the lift (1 m/s2).
Rearranging the formula: R = m(g + a).
Substituting the given values: R = 50 × (9.8 + 1) = 50 × 10.8 = 540 N.
If the lift were stationary or moving at a constant velocity, the weight would be 490 N (50 × 9.8). Because the lift accelerates upward, the person feels heavier.
SIMILAR QUESTIONS
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