does anyone know the answer to this please?

A boy throws a rock from a point A at a height h1= 28.1 meters above the ground towards an obstacle B which is h2=12.8 meters above the ground. With what minimum horizontal velocity 'u' m/s must the rock be thrown in order to have the rock just clear the the obstruction B.Take gravitational acceleration to be 9.81m/s2.

Question

does anyone know the answer to this please?


A boy throws a rock from a point A at a height h1= 28.1 meters above the ground towards an obstacle B which is h2=12.8 meters above the ground. With what minimum horizontal velocity 'u' m/s must the rock be thrown in order to have the rock just clear the the obstruction B.Take gravitational acceleration to be 9.81m/s2.

kainui · Answer

First off, draw a picture with the heights labeled and the direction of throwing labelled to see what is happening and what needs to happen.

anonymous · Answer

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