The 2nd Pulley RPM calculator computes the RPMs of a second pulley based on the the RPMs and Diameter of the first pulley and the diameter of the second pulley.
INSTRUCTIONS: Choose units and enter the following:
(RPM1) RPMs of First Pulley
(D1) Diameter of First Pulley
(D2) Diameter of Second Pulley
2nd Pulley RPMs (RPM2): The calculator returns the rotational velocity of the second pulley in revolutions per minute (RPMs). However, this can be automatically converted to compatible units via the pull-down menu.
The Math / Science
The rotation rate of the two pulleys are interconnected by the fact of a belt or chain running on the perimeter of the two pulleys. This means that the rotation rate of pulley 1 and its diameter will dictate the belt speed. Based on the belt speed and the diameter of the second pulley, you can compute the rotation rate of the second pulley. The formula for the 2nd pulley rotation rate is: