Question

A boy throws a stone upward with a velocity of 60m/s. (a) How long Will It take to reach the maximum height. (taking a = -10m/s2 ) (b) What is the maximum height reached by the ball?

Answer 1

Answer:

so initial velocity of stone (u) = 60m/s , a = -10m/s^2 , g = 10m/s^2

b) maximum height (h) = u^2/2g = 60(60)/2(10) = 180m

a) h = ut + at^2/2

180 = 60(t) + (-10)(t^2) /2

180 = 60t - 5t^2

0 = -5t^2 +60t - 180

0 = -5t^2 + 30t + 30t -180

0 = -5t ( t - 6) +30( t - 6)

0 = ( -5t + 30)(t - 6)

t = 6 sec

Answer 2

Answer:

the above answers is correct