Effects of Electric current By Nitin Oke For Safe Hands Akola www.safehandsakola.org

Effects of electric current Electric current can produce magnetism, which can be verified by deflection of magnetic needle placed in “coil” of wire. This phenomenon was observed by Hans Chritian Orsted.

Facts The magnetic property is seen only if current is flowing. The magnetic property is more if current is more. Magnetic property reduces as the needle is moved away from wire The direction of deflection is reversed if the direction of current is reversed.

Induced electricity Michel Faraday thought that if current can produce magnet then why not magnet will produce current? The current is produced due to motion of magnet ( not just presence of magnet) such current is called as “induced current” and event as “electro magnetic induction”.

Properties of induced current The induced current exist till magnet is moving The direction of induced current depends on direction of moment of magnet. If the magnet approaches the coil faster then more current is induced and if the approach is slow then less current is induced.

Electric motor The magnet due to current was used to produce mechanical energy using electrical energy in electric motor. The phenomenon was simple as if we place a coil in horse shoe magnet and allow current to pass it will rotate due to creation of opposite poles. A “commutator” changes the pole positions of electromagnet due to change in direction of current. So coil keeps on rotating instead of just half rotation.

Electric bell An application of electromagnet is electric bell. It uses simple circuit as shown in figure. Due to completion of circuit the electromagnet attracts the striker, the striker when moves towards the electromagnet it breaks the circuit and hence recoils back due to which circuit is completed and process repeats.

Working of electric bell

Classification of elements All elements can be classified as “Conductors” which conducts electricity Nonconductors or “insulators” which do not conduct electricity Some elements are also called as “semiconductors” which can conduct if temperature is more but don’t at low temperatures

Representation of components While representing electrical circuit following symbols are used. Cell Battery Key Source of Alternating current 

Symbols used in electric circuits Cell Battery Key Source of Alternating current  For Safe Hands By Nitin Oke