A tennis ball, starting from rest, rolls down the hill in the drawing. At the end of the hill the ball becomes airborne, leaving at an angle of `37^(@)` with respect to the ground treat the ball as a thin-walled spherical shell. Q. The velocity of projection `v` isA. `sqrt(2gh)`B. `sqrt((10)/(7)gh)`C. `sqrt((5)/(7)gh)`D. `sqrt((6)/(5)gh)`

A tennis ball, starting from rest, rolls down the hill in the drawing

1.	A tennis ball, starting from rest, rolls down the hill in the drawing. At the end of the hill the ball becomes airborne, leaving at an angle of `37^(@)` with respect to the ground treat the ball as a thin-walled spherical shell. Q. The velocity of projection `v` isA. `sqrt(2gh)`B. `sqrt((10)/(7)gh)`C. `sqrt((5)/(7)gh)`D. `sqrt((6)/(5)gh)`
Answer» `K_("total")` after falling a height `h` is mgh `(K_(R))/(K_(T))=(2)/(3)` `thereforeK_(T)=(1)/(2)mv^(2)=((3)/(5))(mgh)` `thereforev=sqrt((6gh)/(5))`

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