A transformer changes 120 V across the primary to 1200 V across the secondary.If the secondary coil has 800 turns,how many turns does the primary coil have?
A)40
B)80
C)100
D)400
E)4000

Question

Quizplus · Accepted Answer

The transformer's voltage ratio is equal to its turns ratio. Given a secondary voltage of 1200 V and a primary voltage of 120 V, the voltage ratio is 1200/120 = 10. With 800 turns on the secondary, the primary must have 800/10 = 80 turns.

A Transformer Changes 120 V Across the Primary to 1200