The magnitude of an $AC$ voltage used in India is $......$ and its frequency is $......$.

Answer the following questions:
$(i)$ What is the direction of magnetic field lines outside a bar-magnet?
$(ii)$ Why two magnetic field lines cannot intersect each other?
$(iii)$ What is indicated by crowding of magnetic field lines in a given region?
$(iv)$ What is the frequency of $AC$ in India?
$(v)$ State one advantage of $AC$ over $DC$.

Name the type of current:
$(a)$ used in household supply,
$(b)$ given by a cell.

$A$ soft iron bar is introduced inside a current-carrying solenoid. The magnetic field inside the solenoid:

What is the advantage of the third wire of earth connection in domestic appliances?

Explain the meanings of the words "electromagnetic" and "induction" in the term electromagnetic induction. List three factors on which the value of induced current produced in a circuit depends. Name and state the rule used to determine the direction of induced current. State one practical application of this phenomenon in everyday life.