If a fly sits halfway between the axis and the edge of a rotating phonograph turntable, what happens to its tangential speed when the rpm is doubled?

V = 2(pi)r / T 

Where: 
v = linear velocity (speed) 
r = radius from center of the circle 
T = period (usually in seconds) 

Knowing this relationship, we can deduce that T, the period, is inversely proportional to the linear speed. Thus, if the RPM (period) is doubled, then the speed of the fly will doubled also. 

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