A passenger is walking on a walkalator (horizontal escalator) at a speed of 6 km/hr relative to the escalator. He starts from point P on the ground and reaches point Q on the ground. The walkalator is moving at 3 km/hr relative to the ground in the direction of point Q. The distance PQ is 120 m. The time taken by him to reach point Q is:
Correct answer: B. 48 s
- A. 16 s
- B. 48 s
- C. 32 s
- D. 72 s
Explanation
The correct answer is 48 seconds.When the passenger is walking on the moving walkalator, their speed relative to the ground is calculated by adding the speeds of the passenger and the walkalator. In this case, it is 6 km/hr + 3 km/hr = 9 km/hr. Converting this to m/s gives 2.5 m/s. Therefore, the time taken to cover 120m is 120m / 2.5 m/s = 48s.Options A, C, and D are incorrect as they do not consider the concept of relative motion and the addition of speeds. Option B correctly applies these principles to arrive at the correct answer of 48 seconds.
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