The muzzle velocity of a bullet fired from a new rifle is 100 m/s. Neglecting air resistance, at the end of one second a bullet fired straight up into the air will have traveled a distance of
A) (100 - 4.9) m.
B) 100 m.
C) (100 + 4.9) m.
D) 4.9 m.
E) none of these

Question

Quizplus · Accepted Answer

The bullet will have traveled (100 - 4.9) m in one second because it starts with an initial velocity of 100 m/s, and after one second, it would have slowed down due to gravity (9.8 m/s^2), which reduces its upward velocity by 9.8 m/s. Half of this value (4.9 m) is subtracted from the initial velocity to account for the average velocity over the first second, giving a distance of (100 - 4.9) m.

The Muzzle Velocity of a Bullet Fired from a New