A stone dropped from a certain height can reach the ground in 5 seconds. It is stopped after 3 seconds of its fall and then allowed to fall again. Find the time taken by the stone to reach the ground for the remaining distance.
Correct answer: B. 4 s
- A. 2 s
- B. 4 s
- C. 6 s
- D. 8 s
- E. 10 s
Explanation
The stone is initially dropped from a height and falls for 3 seconds before being stopped. During this time, it falls a certain distance which can be calculated using the equation of motion: s = ut + (1/2)gt², where u is the initial velocity (0 m/s), g is the acceleration due to gravity (9.8 m/s²), and t is 3 seconds.After being stopped, the stone falls the remaining distance, which is the difference between the total height and the distance fallen in the first 3 seconds. It takes 4 seconds to fall this remaining distance, calculated using the same equation of motion. Therefore, the correct answer is 4 seconds.The other options are incorrect because they either underestimate or overestimate the time required for the stone to fall the remaining distance.
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