What is the function of an earth wire? Why is it necessary to earth metallic appliances?

State the rules for finding the direction, when :(a) A magnetic field produced around a straight conductor carrying current,(b) The force experienced by a current carrying a straight conductor placed in a magnetic field placed perpendicular to it.(c) current induced in a coil due to its rotation in a magnetic field.

Imagine that you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from the back wall towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of the magnetic field?

When is the force experienced by a current–carrying conductor placed in a magnetic field largest?

List two methods of producing magnetic fields

State whether the following statements are true or false : (a) The field at the center of a long circular coil carrying current will be parallel straight lines. (b) A wire with green insulation is usually the live wire of an electric supply