Question

If a rifle fires a bullet straight up with a muzzle speed of 300 m/s how long will it take for the bullet to reach its apex? Ignore air friction.

Answer 1

use the kinematic equation
v = v + at
0 = 300 + -9.81*t
the first velocity is zero, because at it's apex, the bullet no longer has a speed
the other v is the initial velocity
a is gravity (hence the negative sign)
t is time in seconds