Question

when a particle is thrown vertically upwards its velocity at one third of its maximum height is 10 root 2 m/s .the maximum height attained by it??

Answer 1

v^2 - u^2 = 2aS

According to question
H/3 = [(10√2)^2 - u^2] / (-2g)
H/3 = (u^2 - 200) / (20)
20H/3 = u^2 - 200
u^2 = 20H/3 + 200 ……(1)

For maximum height v = 0
H = u^2 / (2g)
H = (20H/3 + 200) / (20) ……[∵ from (1)]
20H = 20H/3 + 200
40H/3 = 200
H = 1.5 m

Answer 2

Answer:

Explanation:

v^2 - u^2 = 2aS

According to question

H/3 = [(10√2)^2 - u^2] / (-2g)

H/3 = (u^2 - 200) / (20)

20H/3 = u^2 - 200

u^2 = 20H/3 + 200 ……(1)

For maximum height v = 0

H = u^2 / (2g)

H = (20H/3 + 200) / (20) ……[∵ from (1)]

20H = 20H/3 + 200

40H/3 = 200

H = 15m.