Question

solve this fast........

Answer 1

Time taken to reach maximum height is 3s.
Let Initial velocity be u .
Final velocity will be 0 .
Acceleration due to gravity ( in this question ) will be -10 m/s^2( negative sign indicates acceleration in downward direction opposing motion of ball)
Let maximum height travelled by ball be s.

Using 1st equation of motion,
0(v) = u(u) - 10*3 (at)
Simplifying,
U = 30m/s

Using 3rd equation of motion,
0^2( v^2) - 30^2(u^2)=2*-10(a)*s(s)
Simplifying,
S = 45m

Therefore correct answer is option is 4th .