What is meant by mutual induction?

1 Answer

Answer :

The production of induced e.m.f in secondary coil due to change of current in a neighbouring primary coil is called mutual induction.

Related questions

Description : Briefly explain the construction and working of an induction coil.

Last Answer : Construction: An induction coil consists of a primary P having few turns of thick insulated copper wire wound over a soft iron core connected to a battery. It also has a secondary coil S of larger number ... repeats. During the make break of the circuit, large e.m.f is induced in the secondary coil.

Description : What is an induction coil?

Last Answer : Induction coil is a device which is used to obtain high D.C voltage from a low voltage DC source.

Description : Mention the applications of electromagnetic induction.

Last Answer : The three devices which work on the principle of electromagnetic induction are: a) A.C. and D.C. Dynamo b) Transformer c) Induction coil b)

Description : State Faraday's second law of electromagnetic induction.

Last Answer : The Magnitude of the induced e.m.f is directly proportional to the rate of change of magnetic field linking the conductor.

Description : State Faraday’s first law of electro-magnetic induction.

Last Answer : Whenever a magnetic field linked with a conductor changes, an induced e.m.f is generated in the conductor.

Description : Define electromagnetic induction.

Last Answer : The phenomenon in which electro motive force (emf) is induced in the circuit when the magnetic field linked with a circuit changes is called electromagnetic induction.

Description : State the functions of the following components in a dynamo /motor.

Last Answer : a) Commutator: It is used to alter the direction of the current in me coil after every half rotation. b) Carbon brushes: it is used to supply a continuous current to the rotating coil through the commutator.

Description : The secondary coil of a transformer in which the voltage is stepped down are usually made of thicker wire than primary. Why?

Last Answer : The secondary coil is made of thicker wire to sustain larger electric current.

Description : Mention the factors on which the magnitude of the e.m.f induced in the transformer depends.

Last Answer : 1) E.m.f in the primary coil 2) Number of turns in the primary coil 3) Number of turns in the secondary coil 4) The core material

Description : What are primary and secondary coil in a transformer?

Last Answer : The coil which is connected to input source is called primary coil. The coil which is connected to the output source is called secondary coil.

Description : What is a step down transformer?

Last Answer : A transformer which decreases the input voltage of the AC source is called step down transformer.

Description : What is a step up transformer?

Last Answer : A transformer which increases the input voltage of an AC source is called a step up transformer.

Description : On what principle does a transformer work?

Last Answer : Transformer works on the principle of electromagnetic induction.

Description : What is a transformer?

Last Answer : A transformer is a device which is used for increasing or decreasing the AC voltage.

Description : Give reason: Stationary coil and stationary magnet cannot produce induced electric current.

Last Answer : An emf is induced in the coil only when there is relative motion between the coil and the magnet.

Description : A cyclist riding a cycle fitted with a dynamo to a tyre gets bright light in the bulb connected, when he pedals fast. Why?

Last Answer : More magnetic lines of force change with respect to the coil, leading to more current being produced.

Description : What energy conversion does take place in a dynamo when it is in use?

Last Answer : Mechanical energy changes into electrical energy.

Description : In an AC dynamo, the speed at which the coil rotates is doubled. How would this affect a) the frequency of output voltage b) the maximum output voltage?

Last Answer : a) Frequency is doubled b) Maximum output voltage is doubled.

Description : Suggest two ways in an AC dynamo to produce a higher emf.

Last Answer : a) By increasing the speed of rotation of coil b) By increasing the number of turns of the coil.

Description : What is the effect on the magnitude of emf generated in an AC generator if the speed of rotation is increased?

Last Answer : The magnitude of emf generated increases.

Description : What determines the frequency of AC produced in a generator?

Last Answer : The number of rotations of the coil in one second determines the frequency of a AC generator.

Description : Mention the devices that work on AC motor.

Last Answer : Electric fans, electric mixer, electric grinder, washing machine work on AC source.

Description : State Fleming's left hand rule (motor rule).

Last Answer : If the first three fingers of the left hand are held mutually perpendicular to each other such that the finger points in the direction of magnetic filed, the middle finger points in the direction of current, then the thumb points in the direction of mechanical force acting on the conductor.

Description : On what principle does an electric motor work?

Last Answer : An electric motor utilizes the magnetic effect of current. It works on the principle that a conductor carrying current in a magnetic field experiences a mechanical force.

Description : What is an electric motor?

Last Answer : An electric motor is a device that converts electric energy into mechanical energy.

Description : Give reason: A.C cannot be used for electrolysis.

Last Answer : In electrolysis the ionisation of the electrolyte takes place where the positive and negative charges move towards opposite electrodes. But if we pass an alternating current the polarity ... electrode resulting in no ionisation. Hence electrolysis cannot take place with alternating current.

Description : What is a commutator?

Last Answer : The two half rings or split rings used to produce current in the same direction in a DC dynamo is called commutator.

Description : What should be the type of source of electric current to get electric current of constant magnitude?

Last Answer : Direct current

Description : Give reason: Split rings are used instead of slip rings to construct DC dynamo

Last Answer : Split rings make the current to flow in the same direction in the external circuit in both cycles.

Description : What is a DC dynamo?

Last Answer : A dynamo that produces a "direct current" is called DC dynamo.

Description : When is the magnitude of induced current maximum and minimum?

Last Answer : Induced current is maximum when the plane of the coil is perpendicular to the plane of the coil. Induced current is minimum when the plane of the coil is parallel to the plane of the coil.

Description : Mention the uses of alternating current.

Last Answer : 1. Alternating current is used in domestic appliances like lamps, heaters, fans, ovens, radio etc. 2. It is used to produce required frequency of radio waves for radio and T.V transmission ... communication. 4. It is used to produce ultrasonic waves used in industries, ultrasound scanning and SONAR.

Description : What is the voltage and the frequency of the A.C source supplied to our homes and industries?

Last Answer : The voltage range of domestic AC is 230 to 250 volts. The frequency of A.C source is 50 Hz or 50 cycles per second.

Description : How does the armature rotate in the following?

Last Answer : a) Bicycle dynamo: The friction between moving tyre and the cylindrical head of the armature. b) Hydro-electric power station: Turbines rotate by the flow of water. c) Nuclear power reactor: Turbines rotate by the flow of steam. d) Windmills: Turbine rotate by the force of wind.

Description : What an armature?

Last Answer : The coil of insulated copper wire wound over a core of soft iron is called armature.

Description : What is an AC dynamo?

Last Answer : A dynamo that produces an alternating current is called AC dynamo.

Description : On what principle does a dynamo work?

Last Answer : Dynamo works on the principle of electromagnetic induction.

Description : What is a dynamo?

Last Answer : A dynamo is a device which converts mechanical energy into electrical energy.

Description : What should be the angle between the thumb (main) finger and the central finger in Fleming’s rule? What does each finger indicate?

Last Answer : The angle between the thumb and the central finger must be 90o. Fore finger indicates direction of magnetic field, thumb indicates direction of mechanical force / motion of conductor and the central finger indicates the direction of induced current or electric current.

Description : State Fleming's right hand rule or Dynamo rule.

Last Answer : Arrange the first three fingers of the right hand mutually perpendicular to each other; if the fore finger indicates the direction of magnetic field, the thumb in the direction of motion of the conductor, then the middle finger indicates the direction of the induced e.m.f

Description : On what factors does the induced emf in the coil depend?

Last Answer : Induced e.m.f in a coil increases with increase in: a) the number of turns of the coil, b) the strength of the magnetic field c) the speed with which the magnet or the coil moves d) area of the coil

Description : Can a static magnet induce an e.m.f in a stationary coil of wire? Give reasons.

Last Answer : No, when both coil and magnet are stationary, the magnetic field linked with the coil remains constant. Only when the magnetic field linked with the coil changes, current is produced.

Description : What is induced current?

Last Answer : The electric current produced in the circuit when magnetic field linked with a circuit changes is called induced current.

Description : What is a galvanometer? What is its use?

Last Answer : Galvanometer is a device used to measure the electric current flowing through a conductor.

Description : Give reason: In the experiment conducted by Faraday the induced electric current was not DC.

Last Answer : The deflection in the galvanometer was to one side when the magnet was pushed in and the deflection was to opposite side when the magnet was taken out. Hence it was AC and not DC.

Description : State the SI unit of potential difference and emf.

Last Answer : The SI unit of potential difference and emf is volt.

Description : Define e.m.f

Last Answer : The energy required to maintain potential difference between the ends of a conductor is called electro motive force (e.m.f)

Description : Which common devices works on the basis of the principle of mutual induction? -Do You Know?

Last Answer : answer:

Description : Which common devices works on the basis of the principle of mutual induction?

Last Answer : – Transformer

Description : A transformer works on the principle of – (1) Self induction (2) Mutual induction (3) Generator (4) Inverter

Last Answer : (2) Mutual induction