In figure, the angle of inclination of the inclined plane is 30°. Find the horizontal velocity V0 so that the particle hits the inclined plane perpendicularly.

In a direction along the inclined plane,0=V0cos⁡30∘−gsin⁡30∘t⇒t=3V0/gIn a direction perpendicular to incline,−Hcos⁡30∘=−Vsin⁡30∘t−12gcos⁡30∘t2Putting the value of t and solving, we get V0=2gH5.