A boy on the edge of a vertical cliff 20 m high throws a stone horizontally outwards with a speed of 20 m/s. It strikes the ground at what horizontal distance from the foot of the cliff? Use g = 10 m/s² A) 10 m B) 40 m C) 50 m D) 60 m E) none of these

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Quizplus · Accepted Answer

The time taken for the stone to fall 20 m vertically can be calculated using the formula $ t = \sqrt{\frac{2h}{g}} $, where $ h = 20 $ m and $ g = 10 $ m/s². This gives $ t = \sqrt{\frac{2 \times 20}{10}} = 2 $ seconds. The horizontal distance is then $ \text{horizontal speed} \times \text{time} = 20 \, \text{m/s} \times 2 \, \text{s} = 40 \, \text{m} $.

A Boy on the Edge of a Vertical Cliff 20