Question bank/JEE Main/Physics

JEE MainPhysicsModerateProjectile Motion

If the projectile hits the inclined plane perpendicularly when
thrown horizontally with
v0v_{0}, from a tower of height H as shown then
the value of
4gH(v0)2\frac{4gH}{{(v_{0})}^{2}} is 2k. Find k.

Show answer and solution
ay=gcos30∘a_{y} = gcos30^{\circ}
ux=V0cos30∘u_{x} = V_{0}cos30^{\circ}
uy=V0sin30∘u_{y} = V_{0}sin30^{\circ}
Vx=ux+axtV_{x} = u_{x} + a_{x}t
0=V032−g2t0 = \frac{V_{0}\sqrt{3}}{2} - \frac{g}{2}t
t=v03gt = \frac{v_{0}\sqrt{3}}{g}....(i)
Sy=uyt+ayt2S_{y} = u_{y}t + a_{y}t^{2}
(Hcos30∘−0)=V0sin30∘t+12gcos30∘t2(Hcos30^{\circ} - 0) = V_{0}sin30^{\circ}t + \frac{1}{2}gcos30^{\circ}t^{2}....(ii)
From (i) (ii)

⇒4gH(v0)2=10\Rightarrow \frac{4gH}{{(v_{0})}^{2}} = 10

Source: Grass-G / P-16 Physics paper 25 Nov First.docx

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