Final answer:
To zero an M16/A2, one must compensate for the effects of gravity on the bullet's trajectory, which is calculated based on projectile motion. A larger muzzle velocity would reduce the bullet's drop due to gravity while air resistance would increase it.
Step-by-step explanation:
When battlesighting or zeroing a weapon such as the M16/A2, it is necessary to consider how gravity affects the bullet's trajectory. This is because bullets follow a parabolic path due to gravity, so gun sights need to be adjusted to account for this.
(a) To calculate how low the bullet will hit when aimed directly at a target 150.0 m away if the gun is zeroed at 100.0 m, we use the principles of projectile motion. With a muzzle velocity of 275 m/s, the time of flight to 100 m can be found using the formula:
Time = Distance / Velocity
The vertical displacement due to gravity can then be calculated using the formula:
Vertical Displacement = 0.5 × g × Time^2
For a target at 150 m, the time would be longer, and we would calculate the corresponding vertical displacement for that longer time to find out how much lower the bullet will strike.
(b) A larger muzzle velocity would result in the bullet reaching the target more quickly, reducing the time gravity has to act on it, therefore, decreasing the vertical displacement. Air resistance would slow the bullet down, increasing the time in the air and therefore the vertical drop, making the bullet hit lower than expected without air resistance.