Question

A stone is shot out from a catapult with an inital velocity of 30m at an angle of elevation of 60°.find

The time of flight
The maximum height reached
The range

Answer 1

Vi = initial speed up = 30 m/s sin 60 = 26 m/s upward
v = Vi - g t = 26 - 9.81 t
at top v = 0 so t = t = 26/9.81 = 2.65 seconds going up
another 2.65 down so 5.3 seconds in the air
for max h:
h = 0 + Vi t - 4.9 t^2
= 26 * 2.65 - 4.9 * 2.65^2 = 68.9 - 34.4 = 34. meters at top
range = 5.3 seconds in air * 30 cos 60 = 5.3 * 15 = 79.5 meters range