See attached Word file.
Romeo is chucking pebbles as gently as he can up to Juliet's window. That is, he wants the pebbles to hit the window with the least possible speed, as shown in the figure below. He is standing at the edge of a rose garden at H = 7.40 m below her window and at D = 8.60 m from the base of the wall. How fast are the pebbles going when they hit her window?
Let the Romeo throws the pebbles at an angle Q(==theta) with the horizontal and with speed u m/s.
For gentle throw means: H is the highest point of projectile motion, because in that case vertical velocity at top most point (v) will be ...
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