Final answer:
The formula to find the initial velocity of a projectile is vo = v / cos(θ), where v is the total velocity and θ is the angle with the horizontal.
Step-by-step explanation:
The formula to find the initial velocity (vo) of a projectile is given by:
vo = v / cos(θ)
where v is the total velocity of the projectile and θ is the angle it makes with the horizontal.
For example, if a projectile has a total velocity of 20 m/s and an angle of 30 degrees with the horizontal, the initial velocity can be calculated as:
vo = 20 m/s / cos(30°)
vo ≈ 23.1 m/s