A transformer has 50 turns in the primary and 100 in the secondary. If the primary is connected to a `220 V DC` supply, what will be the voltage across the secondary?

A transformer has 100 turns in the primary and 500 turns in the secondary. If the primary is connected to 220V DC supply, then the voltage develop across the secondary will be

A transformer of 100% efficiency has 500 turns in the primary and 10,000 turns in the secondary coil. If the primary is connected to 220V mains supply, what is the voltage across the secondary coil?