The mass of a lift is 500 kg. What will be the tension in its cable when it is moving down under the effect of gravity only? (g = 10 m/s2)
Correct answer: D. 0 N
- A. 5000 N
- B. 50 N
- C. 1000 N
- D. 0 N
Explanation
In this scenario, the lift is moving down purely under the influence of gravity, meaning it is in free fall. During free fall, the only force acting on the lift is gravity, and hence, the tension in the cable is zero. The tension is zero because there is no upward force needed from the cable to alter the lift's motion.As for the other options:5000 N: This would be the tension if the lift was not moving or moving at constant speed upward or downward, but not in free fall.50 N: This is not a valid calculation for this problem.1000 N: This is incorrect as it does not represent any specific calculation relevant to the scenario.
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