What diameter pulley should be installed on an electric motor running at 1,600 rpm to achieve 2,000 rpm on a 10" diameter pulley?

To determine the correct diameter of the pulley to achieve the desired increase in RPM, you can use the relationship between the diameters of the pulleys and their corresponding speeds. This relationship is expressed through the formula that relates the speeds of the pulleys to their diameters:

Speed of Motor Pulley (RPM) × Diameter of Motor Pulley = Speed of Driven Pulley (RPM) × Diameter of Driven Pulley.

In this scenario, you have an electric motor running at 1,600 RPM and a driven pulley that needs to achieve 2,000 RPM with a known diameter of 10 inches. Plugging the known values into the formula allows you to solve for the diameter of the motor pulley.

1. Start by re-arranging the formula to solve for the diameter of the motor pulley:

Diameter of Motor Pulley = (Speed of Driven Pulley / Speed of Motor Pulley) × Diameter of Driven Pulley.

2. Substitute the known values:

Diameter of Motor Pulley = (2000 RPM / 1600 RPM) × 10 inches.

3. This simplifies to:

Diameter of Motor Pulley = (2.5) × 10 inches = 25 inches.

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