The device used for producing electric current is called a

$A$ device used for producing current is:

Which sources produce alternating current?

$(a)$ Describe an activity to determine the direction of magnetic field produced by a current-carrying straight conductor. Also,show that the direction of the magnetic field is reversed on reversing the direction of current.
$(b)$ An $\alpha$-particle (which is a positively charged particle) enters a uniform magnetic field at right angles to it as shown below. Stating the relevant principle,explain in which direction will this $\alpha$-particle move?

$(a)$ What is meant by a 'magnetic field'?
$(b)$ How is the direction of magnetic field at a point determined?
$(c)$ Describe an activity to demonstrate the direction of the magnetic field generated around a current-carrying conductor.
$(d)$ What is the direction of the magnetic field at the centre of a current-carrying circular loop?

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.