Q8 of 126 Page 196

A fan with copper winding in its motor consumes less power as compared to an otherwise similar fan having aluminum winding. Explain.

Copper has a resistivity of 1.72 x 10-8 Ωm whereas aluminum has a resistivity of 2.82 x10-8 Ωm. Since aluminum has a higher resistivity, more power is lost in heat than used to run the fan than copper and hence copper wound motor fans consume less fans than aluminum wound motor fans.


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