A rock is thrown horizontally from a tower at point A and hits the ground 3.5s later at point B. The line from A to B makes an angle of 50 degrees with the horizontal. Compute the magnitude of the initial velocity of the rock.
Step 1. Let the Vi or Initial Velocity= u m/sec
Vertical Distance travelled = 1/2 a t^2 = 0.5*9.8*t^2
= 4.9*(3.5)^2 = 60.025 m
Step 2. Get the u
tan50 = 60.023/3.5u
ANSWER: u = 14.39 m/sec