State various effects of electric current and explain any one.

2 Answers

Answer :

Heating effect : When an electric current flows through a conductor, the flow of electron is opposed by the resistance of conductor and heat is produced. Joules law of heating.  It is utilized in electric irons, water heaters, Hot plates, electric lamps etc. 


Chemical effect : Whenever a DC current is passed through a chemical solution, the solution is decomposed into its constituent substances. It is utilized in the electrolytic processes such as electro-plating, electro-refining, in production of different chemicals etc. 


Magnetic Effect: Whenever a conductor carries electric current, the magnetic field is produced. If the conductor is a straight conductor, the magnetic field is produced round the conductor itself. If the conductor is in the form of coil or winding (solenoid) wound over the core, the magnetic field is produced in the core. 

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Answer :

Effects of Electric Current: 

1. Magnetic Effect: When a current is passed through a conductor, magnetic field is produced round the conductor. Due to this field when current carrying conductor is placed in a magnetic field it experiences a mechanical force. When we bring one permanent magnet near to another electromagnet then there is a force of attraction or repulsion depending on the direction of current in the coil of electromagnet. 


2. Heating effect: When current is passed in the conductor, heat is produced which is proportional to I 2Rt , where I is current flowing in conductor, R is resistance of conductor and t is time duration of current flow. The current to be measured is passed through a small element which heats due I 2Rt power loss. The rise in temperature is converted into elongation of hot wire element causes displacement of pointer. 

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