निम्नलिखित घटकों में से कौन सा DC मशीन का बाहरी सुरक्षात्मक ढांचा या आवरण बनाता है?

In a three-phase alternator, the factor that accounts for the reduction in induced EMF because the coils within a phase group are spread across several slots per pole is known as the ________.

Which factor is least significant in determining the rating of a distribution transformer?