This is used for exploring the concept of electromagnetic induction.
It comprises of 2 coils, primary coil wound from thicker gauge enameled copper wire with lesser number of turns; and a secondary coil wound from a thinner gauge fine enameled copper wire, with more number of turns.
Both wires are wound on an insulated plastic former and fitted with 4mm sockets.
The primary wire has an approximate resistance of 0.5 ohms and is wound on a former whose dimensions are 110×30 mm (length × diameter).
The secondary coil has an approximate resistance of 100 ohms and is wound on a former whose dimensions are 120×82 mm (length × diameter).
The primary coil slides into the secondary for electromagnetic coupling.
It includes a soft iron cylindrical core that slides into the primary and its dimensions are 160×15 mm (length × diameter).
Students can appreciate that how when the direct current is switched on and off in the primary coil, by the make and break mechanism, it produces the changes of current and changes of magnetic field which are necessary for an electromagnetic induction to occur in the secondary coil.