Question

a ball is thrown vertically upwards and reaches a maximum height in 3 seconds. Find :

(a)The velocity with which it wasthrown upwards.(b)the maximum height attained by the ball

Answer 1

v = 0 (at max height)

t = 3 sec

a = 10 m/s²

Find u and s.

1st equation of motion:

v = u + at

0 = u - 10 (3) (- sign because a is in opposite direction of u)

u = 30 m/s

v²-u² = 2as

0 - (30)² = 2 (-10) s

900/20 = s

s = 45 m