Question

Rifle and Bullet A rifle is aimed horizontally at a target 33 m away. The bullet hits the target 1.3 cm below the aiming point. Neglect air resistance. (a) What is the bullet's time of flight? s (b) What is its speed as it emerges from the rifle? m/s

Answer 1

Answer:

(a) 0.052 seconds

(b) 640.7 m/s

Explanation:

horizontal distance, x = 33 m

vertical distance, y = 1.3 cm = 0.013 m

(a) Let the time of flight is t.

Use second equation of motion

h = ut + 1/2 at^2

0.013 = 0 + 0.5 x 9.8 x t^2

t = 0.052 seconds.

(b) Let the speed of the bullet as it emerges from the rifle is u.

Horizontal distance = horizontal velocity x time

33 = u x 0.052

u = 640.7 m/s