Velocity
v = velocity
vo = velocity original
f = force
m = mass (of projectile)
t = time total(in seconds)
v - vo = (f/m)t
Distance
x = distance
xo = position of x @ to (usually 0)
t = time total (in seconds)
to = starting time (usually 0)
g = gravity, acceleration of (9.802 ms2, or 32.16 ft.sec2
vo = velocity original
x = xo + (vot) - 1/2(gt2)

And we can simplify to below, becuase we assume xo = 0.

x = (vot) - 1/2(gt2)

And we can simplify to below, becuase we assume vo = 0. Since we assume the projectile starts motion from a standstill.

x = 1/2(gt2)
Projectile Motion Description - It's ok, I don't understand this either.
g = gravity, acceleration of (9.802 ms2, or 32.16 ft.sec2
z = vertical rise of projectile (height)
vzo = velocity, original, in the z-axis (height)
vxo = velocity, original, in the x-axis (distance)
z = (vzo/vxo) - 1/2(g/vxo2)x2
Maximum Altitude Achieved
zm = maximum altitude
vzo = velocity, original, in the z-axis (height)
vxo = velocity, original, in the x-axis (distance)
zm = (vzo2)/2g
Maximum Distance Achieved
xm = maximum distance
vzo = velocity, original, in the z-axis (height)
vxo = velocity, original, in the x-axis (distance)
g = gravity, acceleration of (9.802 ms2, or 32.16 ft.sec2
xm = 2(vzovxo/g)
Equation of Trajectory
z = height
b = frictional force constant (air resistance)
g = gravity, acceleration of (9.802 ms2, or 32.16 ft.sec2
m = mass of projectile
vzo = velocity, original, in the z-axis (height)
vxo = velocity, original, in the x-axis (distance)
z = {(mg/bvxo)+(vzoxo)}x-{m2g/b2ln (mvxo/[mvxo-bx])}


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