ISRO Technician-B Electrician Question Paper - 2019 (Set - 1) with Answer Key

Ceiling fans are measured by the full size of their blade span (also called blade sweep), which is the diameter of the circle that you see when the fan blades are in motion. Or, in other words, fan blade span reaches from the tip of one fan blade to the tip of the blade directly across, also Sweep of ceiling fan refers to double the distance from centre of motor to tip of the blade.

Ns=(120xFrequency)/Number of Poles

Ns=(120×50)/12=500