A bullet fired vertically upwards reaches a height of 500m. Neglecting air resistance, calculate the magnitude of the initial velocity of the bullet. [g = 10ms-2]
-
A.
500.0ms-1 -
B.
100.0ms-1 -
C.
70.0ms-1 -
D.
50.0ms-1
Correct Answer: Option B
Explanation
V2 = U2 + 2gs
V2 = 0
V2 = 2gs
h = 500m
g = 10ms-2
V2 2 x 10 x 500
V2 = 10,000
V = (sqrt{10000})
V = 100ms-1