Answer:
Velocity (magnitude) is 98.37 m/s
Explanation:
We use the vertical component of the initial velocity, which is:
Using kinematics expression of vertical velocity (in y direction) for an accelerated motion (constant acceleration, which is gravity):
Now we need to find as a function of . We use the horizontal velocity, which is always the same as follow:
We know the angle at 3 seconds:
Substitute in and then solve for
With this expression we go back to the kinematic equation and solve it for initial speed