Calculating Pressure for a Moving Part: 285 RPMs on a 4 Inch Cylinder

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To calculate the force on a moving part weighing 1/2 oz spinning at 285 RPM around a 4-inch cylinder, the formula F = Mv²/r is used. First, convert the weight from ounces to slugs, resulting in approximately 0.0009625 slugs. The circumference of the cylinder is about 25.13 inches, leading to a velocity of 9.9465 ft/sec when adjusted for RPM. By substituting the values of mass, velocity, and radius into the formula, the force can be determined in pounds. This calculation provides the necessary information to understand the pressure exerted by the moving part.
RanMan
I am currently try to figure out the amount of pressure on a moving part that weights about an 1/2 oz. It spins at a rate of 285 rpms around the outside of a 4 inch cylinder.
I'm sure there has to be a formula of some sort that can assist in this calculation. Thanks for any help you may be able to give.

Thanks,
RanMan
www.prewettmills.com[/URL]
 
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F= Mv²/r

where M is the mass of the object,

v is it's velocity

r the radius

You'll have to convert oz to mass units and find the object's velocity from the radius and rpm.
 
Janus, I appoligize for the detailed questions but I know absolutely nothing about physics.
I do not know how to determine the velocity nor do I know how to convert ounces to mass. I'm sorry for not knowing a thing about physics.
All I know is the information that i need which is the force.

Thanks,
RanMan
www.prewettmills.com[/URL]
 
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Well the unit of mass in the FPS system is the slug, and a one slug mass would weigh 32.175 lbs, and there are 16 ounces to a lb.

so mass = 1/(32.175x16)/2 = .0009625 slug.

The circumfernce of a circle of radius 4 in. is 2*4* pi = 25.13 in. or 2.094 ft.

This is the distance the object travels in one revolution. it does this 285 times per min, so its velocity is 2.094*285 = 596.79 ft/min.

divide this by 60 to get ft/sec for 9.9465 ft/sec and you have v

thus
r = .33333 ft
M= .0009625 slugs
v= 9.9465 ft/sec

plug them into the formula, and you'll get the force in pounds.
 
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