A stone is dropped from the top of tower. If its velocity at the mid point of height of tower is 10ms^(-1), then the height of a tower is ..... (g = 10 ms^(-2))

A stone is dropped from the top of tower. If its velocity at the mid p

1.	A stone is dropped from the top of tower. If its velocity at the mid point of height of tower is 10ms^(-1), then the height of a tower is ..... (g = 10 ms^(-2))
Answer» 10 16 8 20 Solution :Suppose initial speed of BALL is `v _(0)` and maximum height is h. Now, for first half distance `d = (h)/(2)` `2AD =v ^(2) -v _(0) ^(2)` `2 xx (-10 ) h/2 = (10) ^(2) - v _(0) ^(2)` `therefore -10 h = 100 -v_(0) ^(2)` `therefore - 10h -100 =- v_(0) ^(2) ""...(1)` Now for maximum height `d = h, v _(0) = v _(0), v =0,` `a = 10 ms ^(-2)` `therefore 2ad =v ^(2) -v_(0) ^(2)` `therefore - 2 xx 10 xx h = 0- v _(0) ^(2) ` `therefore -20h =-v _(0) ^(2) ""...(2)` From equation (1) and (2), `-20 h =- 10h -100` `therefore -10 h =-100` `therefore h = 10M`