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

Answer 1

v = Vi - 9.81 t
at top v = 0
so
t = 700/9.81 = 71.4 s
now there are two ways to proceed
one way:
h = Vi t -4.9 t^2
h = 700(71.4) - 4.9(71.4)^2
h = 25,000 m

other way;
average speed up = (700+0)/2 = 350 m/s
h = 350*71.4 = 25,000 m