Name some devices in which electric motors are used.

The branch of science that covers the comprehensive study of electricity and magnetism is known as $.........$.

Which instrument works on the principle of 'Electromagnetic induction'?

$(a)$ Describe an activity to show the pattern of magnetic field lines of a bar magnet,with the help of a cardboard piece and iron filings.
$(b)$ Compare the magnetic field of a bar magnet with that of a current-carrying solenoid with the help of a figure.

In our daily life,we use two types of electric current whose current-time graphs are given below:
$(i)$ Name the type of current in two cases.
$(ii)$ Identify any one source for each type of current.
$(iii)$ What is the frequency of current in case $(b)$ in our country?
$(iv)$ On the basis of these graphs,list two differences between the two currents.
$(v)$ Out of the two,which one is used in transmitting electric power over long distances and why?

What does the direction of the thumb indicate in the Right-Hand Thumb Rule? In what way is this rule different from Fleming's Left-Hand Rule?