The factor by which, the induced E.M.F gets reduced due to short pitching is called pitch factor or coil span factor denoted by Kc. It is given as Kc = cosα/2 given α = 60° Kc = cos60/2 Kc = cos30° Kc = √3/2
The melting point of Eureka is 1221 to 1300 °C The melting point of Kanthal is 1,425 °C The melting point of Nichrome is 1400 °C The melting point of Graphite is 3,600°C Hence Eureka has the least range of temperature.
Lap Winding:-In a lap winding the number of parallel paths (a) is always equal to the number of poles (p) and also to the number of brushes. In the given question number of poles is 4 hence the number of brushes will be 4. Wave Winding:- In wave windings, the number of parallel paths (a) is always two and there may be two or more brush positions.
EXAMIANS