कौन सा ट्रांसफॉर्मर कूलिंग प्रकार बिना किसी बाहरी पंखे के प्राकृतिक संवहन पर निर्भर करता है?

In which unit is the power rating of a transformer expressed?

In a transformer, it is generally preferred to wind the low-voltage winding close to the core and the high-voltage winding over the low-voltage winding. What is the primary advantage of this type of arrangement?