Question

A bullet blasts from the barrel of a gun upward in the vertical direction with an initial speed of 700 m/s . Find the maximum altitude reached by this bullet and the time needed to reach it

Answer 1

The maximum altitude that the bullet will reach is the point at which its velocity is zero. The equation that may be used in order to determine the altitude is,

                                   D = ((Vi)2 – (Vf)2)/2g

Where Vi and Vf are the initial and final velocities, respectively. g is the deceleration due to gravity.

Substituting the known values,

                                    D = ((700 m/s)2 – (0 m/s)2) / (2(-9.8 m/s2))

                                    D = 25000 m

 

Thus, the maximum height is 25000 m.

 

For the time needed to reach it, we use the equation,

                                    Vf = Vi – (g)(t)

Substituting,

                                    0 = 700 m/s – (-9.8 m/s2)(t)

The value of t is equal to 71.43 s.