Anybody know the formula for the Magnus Effect?

AI Thread Summary
The discussion centers on the search for a formula related to the Magnus Effect, particularly in the context of modeling golf ball trajectories for a physics experiment. The original poster, Tony, shares a formula he derived for calculating the force due to the Magnus Effect, which incorporates variables like density, angular velocity, and horizontal velocity. He attempts to adapt a cylinder formula to a sphere, ultimately presenting a revised equation. Participants are encouraged to verify the formula against established sources, such as Wikipedia, which provides additional information on the Magnus Effect and relevant coefficients. The conversation emphasizes the importance of accurate modeling in physics experiments.
plutonyum94
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I realize I may way out of my depth here...
but i thought i'd jump in anyway.

so that's the question...is there a specific formula?

feel free to call me an idiot if I've got this all wrong :P

Cheers
Tony

EDIT:

sorry, i forgot a bit of background...
so I'm doing a physics experiment revolving around modelling true golf ball trajectories. the magnus effect plays a pretty large role, and in my hpothesis, i'd like to create a formula factoring it in.



EDIT2:
ok, so i THINK I've found a formula...
i don't know how everyone else gets the cool symbols, so I am just going to use regular letters. sorry if its confusing...

Fm = 2pi(p)(w)(vx)(h r^2)

where p = density at 25 degrees C, w = angular velocity, vx - horizontal velocity and h r^2 = height of cylinder multiplied by the radius squared.

this formula is for a cylinder.
i've rearranged it:
Fm = 2(p)(w)(vx)(pi r^2 h)

now, as far as i can remember, pir^2h is the formula for the volume of a cylinder...
as I am looking at golf, I've taken out that formula and replaced it with the formula for the volume of a sphere:

Fm = 2(p)(w)(vx)(4/3pi r^3)

which eventually, returns the pi to the front:

Fm = 8pi(p)(w)(vx)(r^3)
3

^^ that's divided by 3, btw.

ok, so is THIS is viable formula?
 
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I don't know where that formula came from, but have you checked Wikipedia's article on the magnus effect? See:

http://en.wikipedia.org/wiki/Magnus_effect

There's a formula, along with typical values of the lift coefficient.
 
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