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I am attempting to create an excel worksheet that accurately predicts the trajectory of a projectile.

Anyways, I am having some trouble with calculating wind along the Z axis, left or right of the target.

Y axis is up in the air

X axis is towards the target

Z axis is left or right of target

Fd = force of drag

Fw = force of wind

Fb = force applied on golf ball

p = Rho, density of air

Cd = Drag coefficient

V = velocity

A = Area, which for a sphere I am using A = PI(Diameter)^2 /4

m= mass of golf ball

a = acceleration of ball

t = time

z = distance off from z-axis

Force of wind(Fw) ->

<- Force of drag(Fd)

I am using,

Fd = 1/2*p*Cd*V^2*A

So,

Fw = 1/2*p*Cd*Vw^2*A

Vw = simply wind speed, Fw is constant

and

Fd = 1/2*p*Cd*Vd^2*A

Vd = Fw / mass * time

then

Fw - Fd = Fb

Fb = force applied on ball

Fb/mass = acceleration of ball

then

z = Vot + 1/2at^2

I am getting an acceleration that is roughly constant since I am dealing with low wind speeds and short time of flight. However, I am getting extremely low #'s for the distance the ball strays off on Z axis. I get the same answer if I use a constant acceleration or time stamps.

Information with just variables is fine with me, but if you want the data for some reason...

mass of golf ball = 0.04593

diameter of golf ball = 0.04267

Wind velocity = .44704 m/s

Rho = 1.1735 kg/m^3

Cd = .3878

time of flight = 1 sec

I am getting 0.0007221 meters off on z-axis.

Not sure where I am going wrong... Any help would be much appreciated.

Anyways, I am having some trouble with calculating wind along the Z axis, left or right of the target.

Y axis is up in the air

X axis is towards the target

Z axis is left or right of target

Fd = force of drag

Fw = force of wind

Fb = force applied on golf ball

p = Rho, density of air

Cd = Drag coefficient

V = velocity

A = Area, which for a sphere I am using A = PI(Diameter)^2 /4

m= mass of golf ball

a = acceleration of ball

t = time

z = distance off from z-axis

Force of wind(Fw) ->

<- Force of drag(Fd)

I am using,

Fd = 1/2*p*Cd*V^2*A

So,

Fw = 1/2*p*Cd*Vw^2*A

Vw = simply wind speed, Fw is constant

and

Fd = 1/2*p*Cd*Vd^2*A

Vd = Fw / mass * time

then

Fw - Fd = Fb

Fb = force applied on ball

Fb/mass = acceleration of ball

then

z = Vot + 1/2at^2

I am getting an acceleration that is roughly constant since I am dealing with low wind speeds and short time of flight. However, I am getting extremely low #'s for the distance the ball strays off on Z axis. I get the same answer if I use a constant acceleration or time stamps.

Information with just variables is fine with me, but if you want the data for some reason...

mass of golf ball = 0.04593

diameter of golf ball = 0.04267

Wind velocity = .44704 m/s

Rho = 1.1735 kg/m^3

Cd = .3878

time of flight = 1 sec

I am getting 0.0007221 meters off on z-axis.

Not sure where I am going wrong... Any help would be much appreciated.

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