For higher values of voltages the window space factor of the transformer

For higher values of voltages, the window space factor of the transformer:

1. Increases
2. Decreases
3. Remains constant
4. Any of above

Correct answer: 2. Decreases

From mathematical formula of transformer window space factor:

kW = 10/(30 + kV_hv)

With an increase in voltage, the window space factor decreases.