The RPMs of the 4th pulley on 3 shafts equation calculates the RPMs of a pulley when the RPM and Diameters are known for a series of pulleys on three axles (see diagram).
INSTRUCTIONS: Choose units and enter the following:
RPMs of the 4th Pulley on axle 3(RPM4): The calculator returns the Revolutions Per Minute. However, this can be automatically converted to compatible unit via the pull down menu..
The formula to compute the rotation rate of a fourth pulley on a three axle system is:
`RPM_4 = (RPM_1 * (D1 * D3))/(D2*D4)`