IGCSE physics transformers Power Loss

What causes a flow of current in the secondary coil?

• electromagnetic induction in the core

• current flows in the core

• electrons flow from the primary coil to the secondary coil

• there is a potential difference between the coils

Why do we use transformers?

• For safety reasons

• we want high current where ever possible

• we don't like high voltage

• most devices need high current

Which is better?

• low power loss

• high power loss

• infinite power loss

• 50% power loss

What is the equation for power loss?

• None of the above

What is the voltage of electricity coming into the home in China?

• 110V

• 220V

• 33V

• 50V

Which kind of transformer is this?

• a step up transformer

• a step down transformer

• no step transformer

• none of the above

The voltage going into a transformer is 100kV and we require 220V. There are 50000 turns on the primary coil. How many turns are on the secondary coil?

• 110

• 5000

• 40

• 220