Question

Robebobeccoba fires a bullet from a gun while aiming at a target 149 m away. If the

bullet misses the target by 1 m, what is the horizontal velocity of the bullet?

Answer 1

Answer:

329.6 m/s

Explanation:

The bullet has a projectile motion, consisting of two separate motions:

- A horizontal motion with constant velocity

- A free fall motion (constant acceleration) in the vertical direction

The bullet misses the target vertically by 1 m: this means that 1 m is the vertical dispalcement of the bullet. So we can find the total time of the flight by using the suvat equation

$s=ut+\frac{1}{2}at^2$

where

s = 1 m is the vertical displacement

u = 0 is the initial vertical velocity

$a=g=9.8 m/s^2$ is the acceleration due to gravity

t is the time

Solving for t,

$t=\sqrt{\frac{2s}{a}}=\sqrt{\frac{2(1)}{9.8}}=0.452 s$

The horizontal motion is at constant speed, which is given by

$v_x = \frac{d}{t}$

where

d = 149 m is the distance covered by the bullet

t = 0.452 s is the time taken

Substituting,

$v_x = \frac{149}{0.452}=329.6 m/s$