Two coils of insulated copper wire are wound over a non-conducting
cylinder as shown. Coil 1 has comparative large number of turns. State
your observations, when
(i) Key K is closed.
(ii) Key K is opened.
Give reason for each of your observations
(Also, BE out on 20 November )
Answers
ANSWER
(i)(a) A momentary deflection is shown by the galvanometer.
(b) A momentary deflection is shown by the galvanometer but in the opposite direction.
(ii) When key is closed or opened, the current in the coil I change, therefore the magnetic field linked with coil II changes and hence a current is induced in it.
(iii) The electromagnetic induction-The process by which a changing magnetic field in a conductor induces a current in another conductor.
(iv) Primary coil - coil I Secondary coil - coil II
(v) Fleming's Right-Hand Rule: Stretch the first three fingers of the right hand mutually perpendicular to each other such that the forefinger gives the direction of magnetic field and the thumb points in the direction of the motion of a conductor then, the middle finger will give the direction of the induced current