Explain the meaning of the word 'Electromagnetic' and ‘Induction' in the term 'Electromagnetic Induction’. On what factors does the value of induced current produced in a circuit depend? Name and state the rule used of determination of direction of induced current. State one practical application of this phenomenon in everyday life. (This is a 5 mark question).

Asked by kumarasia | 14th Sep, 2015, 07:24: PM

Expert Answer:

The process by which a changing magnetic field in a conductor induces a current in another conductor is called electromagnetic induction.

By moving a magnet towards or away from a coil. We take a coil with several turns and it is connected to a sensitive galvanometer. When a bar magnet is moved towards the coil, we see a deflection in the galvanometer. This deflection dies down after some time. The deflection is because of the induced current.

Hence, the value of induced current produced in a circuit depends on the following factors:

  1. number of turns in given coil
  2. area of each turn in given coil
  3. rate of change of magnetic field

The rule used of determination of direction of induced current is Fleming's right-hand rule.

Fleming's right-hand rule: Stretch the thumb, forefinger and middle finger of the right hand so that they are perpendicular to each other. If the forefinger indicates the direction of the magnetic field and the thumb shows the direction of motion of the conductor, then the middle finger will show the direction of induced current. This is called Fleming's right-hand rule.

Electrical generator is one of the practical application of this phenomenon in everyday life

 

Answered by Priyanka Kumbhar | 15th Sep, 2015, 09:10: AM