What is vertical velocity; is that vfy or viy?

NO!! for physics

at sixflages in gurnee in illinois….

. If a “projectile” (e.g. a missile) is launched with a given “angle of elevation” ( Θ ) it tends to follow a parabolic arc of motion. . The precise shape of the parabola can be deduced by vector analysis.
In the absence of any gravitational field (or other force), the projectile would continue to move in a straight line indefinitely, however, the gravitational forces cause the parabolic deviation away from the “ideal” straight line. . One way of tackling the vector analysis is to resolve the actual motion into a “horizontal component” and a “vertical component”. . If the initial velocity vector is given by ν , at elevation angle = Θ . then the horizontal component is v cos(Θ) , . and the vertical component is v sin(Θ)

[ sometimes represented in “complex number form” as i v sin(Θ) where i is the square root of minus one - the ‘ i ‘ has the effect of shifting the vector from the ‘horizontal’ x-axis direction, through 90° (in the complex plane) so that it coincides with the ‘vertical’ y-axis direction ]. .

– Best wishes - Majikthise. .

Vertical velocity is vfy

The formula i think will be:

a= (vfy-viy)/t vfy = at+ viy