A bullet fired vertically upward from a gun held 2.0 m above the ground reaches its maximum height in 4.0s. calculate its initial velocity.
[g = 10ms\(^-2\)]
A
10 ms-1
B
8 ms-1
C
40 ms-1
D
20 ms-1
Verified Correct Answer: C.
Step-by-Step Mathematical Solution
At maximum height, the final velocity, v = 0
thus from v = u - gt
0 = u - gt
∴ U = at = 10 x 4 = 40 mls
Source: WAEC / JAMB / NECO Classroom Archive (Record #14140)