Two inclined planes OA and OB of inclinations to the horizontal are α and β , each equal to 3 0 ∘ as shown in the figure. A particle is projected at an angle of 9 0 ∘ with plane OA from point A and it

Question

Two inclined planes OA and OB of inclinations to the horizontal are $α$ and $β$ , each equal to $3 0^{\circ}$ as shown in the figure. A particle is projected at an angle of $9 0^{\circ}$ with plane OA from point A and its strikes the plane OB at point B normally. Then find the speed of projection in m/s. (given that $OA = OB = 20 cm$ and $g = 10 m / s^{2}$ )

TestHub · Accepted Answer

​ Since α = β ​ A O = BO = 20 cm ​ A B = d 2 + d 2 − 2 d ⋅ d cos 12 0 ∘ ​ ​ A B = 3 ​ d ​ Now A B is the range of the projectile from A to B . ​ 3 ​ d = g u 2 sin 2 θ ​ ​ ⇒ 3 ​ d = 2 g u 2 3 ​ ​ ​ Putting d = 0.2 m U = 2 m / s

Physics - Gravitation Question with Solution | TestHub

Doubts & Discussion