It will be 4 times of original thus maximum speed would be 80cm/s
Air resistance is ignored.
g = 9.8 m/s².
At maximum height, the vertical velocity is zero.
Let h = the maximum height reached.
Let u = the vertical launch velocity.
Because ot takes 5.0 seconds to reach maximum height, therefore
(u m/s) - (9.8 m/s²)*(5 s) = 0
u = 49 m/s
The maximum height reached is
h = (49 m/s)*(5 s) - (1/2)*(9.8 m/s²)*(5 s)²
= 122.5 m
Answer: 122.5 m
