Question

15. A stone is projected in air. Its time of flight is 3 s and
range is 150 m. Maximum height reached by the stone is
(g = 10 ms)
(a) 37.5 m
(b) 22.5 m
(c) 90 m
(d) 11.25 m​

Answer 1

Answer:

Time of flight T is

T = 2usinθ/g

3 * 10 /2 = usinθ

usinθ = 15….........…..... (1)

Range = ucosθ x T

150 = ucosθ x 3

ucosθ = 50.....................(2)

Using 1 and 2

tanθ = 3/10

According to relation

R/H = tanθ/4

H = R*tanθ/4 = 150 x 3/40 = 11.25m

Option d

Answer 2

Answer:

so right option is d 11.25m