a stone falls from a cliff and travels 24.5m in the last second before it reaches the ground at the foot of the cliff. find the height of the cliff.
Answers
Answered by
117
Answer:
Explanation:
=> The total time taken by stone to fall from a cliff is suppose t then distance traveled in t seconds will be:
D_t = ut + 1/2 at²
D_t-1 = u(t-1) + 1/2 a(t-1)²
=> distance traveled in 1 sec less from total time thus, distance traveled in last second will be :
D_t - D_(t-1) = u + 1/2 a (2t - 1) = 24.5
1/2 * 9.8 *(2t - 1) = 24.5
as u= 0
t = 3 sec
=> height of cliff will be the total distance traveled during this time. Thus,
H = ut + 1/2 at²
= 0 + 1/2 * 9.8 * (3)²
= 44.1 m
Hence, the height of the cliff is 44.1 m.
Answered by
39
Answer:
Amswer is given above.
Attachments:
Similar questions