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Why the induced emf is also called as ba...

Why the induced emf is also called as back emf?

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**Step-by-Step Solution:** 1. **Understanding Induced EMF**: Induced EMF (Electromotive Force) is generated in a circuit when there is a change in magnetic flux through that circuit. This phenomenon is described by Faraday's Law of Electromagnetic Induction. 2. **Cause of Induction**: The induced EMF arises due to a change in current or magnetic field in the surrounding environment. When the current changes, it alters the magnetic field, which in turn changes the magnetic flux linked with the circuit. 3. **Opposition to Change**: According to Lenz's Law, the direction of the induced EMF is such that it opposes the change in magnetic flux that produced it. This means that the induced EMF works against the source of the original EMF that caused the current change. ...
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Induced abortion is also called .

Express the induced emf as scalar triple product of vecv, vecB and vecl .

A: At any instant, if the current through an inductor is zero, then the induced emf will also be zero. R: In one time constant, the current flows to 37 percent of its maximum value in a series LR circuit.

Asseration: The direction of induced e.m.f. is always such as to oppose the change that causes it. Reason: The direction of induced e.m.f. is given by Lenz's Law.

Assertion If a loop is placed in a non-uniform (with respect to position) magnetic field, then induced emf is produced in the loop. Reason In a non-uniform magnetic field, magnetic flux passing through the loop will change. Therefore, induced emf is produced.

A fan operates at 200 volt (DC) consuming 1000W when running at full speed . It's internal wiring has resistance 1 Omega . When the fan runs at full speed , its speed becomes constant. This is because the torque due to magnetic field inside tha fan is balanced by the torque due to air resistance on the blades of the fan and torque due to friction between the fixed part and the shaft of the fan. The electrical power going into the fan is spent (i) in the internal resistance as heat, call it P_(1)(ii) in doing work against internal friction and air resistance producing heat, sound etc. call it P_(2) . When the coil of fan rotates, an emf is also induced in the coil. This opposes the external emf applied to snd the current into the fan. This emf is called back-emf,call it 'e' . Answer the following questions when the fan is running at full speed. The value of power P_(2) si

A fan operates at 200 volt (DC) consuming 1000W when running at full speed . It's internal wiring has resistance 1 Omega . When the fan runs at full speed , its speed becomes constant. This is because the torque due to magnetic field inside tha fan is balanced by the torque due to air resistance on the blades of the fan and torque due to friction between the fixed part and the shaft of the fan. The electrical power going into the fan is spent (i) in the internal resistance as heat, call it P_(1)(ii) in doing work against internal friction and air resistance producing heat, sound etc. call it P_(2) . When the coil of fan rotates, an emf is also induced in the coil. This opposes the external emf applied to snd the current into the fan. This emf is called back-emf,call it 'e' . Answer the following questions when the fan is running at full speed. The value of power P_(1) is

A fan operates at 200 volt (DC) consuming 1000W when running at full speed . It's internal wiring has resistance 1 Omega . When the fan runs at full speed , its speed becomes constant. This is because the torque due to magnetic field inside tha fan is balanced by the torque due to air resistance on the blades of the fan and torque due to friction between the fixed part and the shaft of the fan. The electrical power going into the fan is spent (i) in the internal resistance as heat, call it P_(1)(ii) in doing work against internal friction and air resistance producing heat, sound etc. call it P_(2) . When the coil of fan rotates, an emf is also induced in the coil. This opposes the external emf applied to snd the current into the fan. This emf is called back-emf,call it 'e' . Answer the following questions when the fan is running at full speed. The value of power P_(1) is

A fan operates at 200 volt (DC) consuming 1000W when running at full speed . It's internal wiring has resistance 1 Omega . When the fan runs at full speed , its speed becomes constant. This is because the torque due to magnetic field inside tha fan is balanced by the torque due to air resistance on the blades of the fan and torque due to friction between the fixed part and the shaft of the fan. The electrical power going into the fan is spent (i) in the internal resistance as heat, call it P_(1)(ii) in doing work against internal friction and air resistance producing heat, sound etc. call it P_(2) . When the coil of fan rotates, an emf is also induced in the coil. This opposes the external emf applied to snd the current into the fan. This emf is called back-emf,call it 'e' . Answer the following questions when the fan is running at full speed. The value of power P_(2) si

The phase difference between the flux linkage and the induced e.m.f. in a rotating coil in a uniform magnetic field

AAKASH SERIES-ELECTROMAGNETIC INDUCTION-Exercise (Very Short Answer Questions)
  1. Name the scientist associated with the direction of induced current.

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  2. State Lenz's law.

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  3. Why the induced emf is also called as back emf?

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  4. What is the basic cause of induced emf?

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  5. Does Lenz's law violate the law of conservation of energy?

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  6. Does Lenz's law hold for an open circuit

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  7. Consider a cube ABCGHIJK of sides a placed in a uniform magnetic field...

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  8. Who discovered eddy current?

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  9. What is an ideal inductor?

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  10. Name the quantity that plays an identical role in an electrical circui...

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  11. The induced e.m.f. in a coil does not depend on

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  12. Name two factors on which the self-inductance of an air-core coil depe...

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  13. What is the effect of metallic core on self inductance?

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  14. Why inductors are made of copper?

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  15. Name two factors on which mutual inductance between a pair of coils de...

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  16. If two coils are very tightly would one over the other, will M increas...

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  17. What are the dimensions of L/R?

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  18. Why the inductance per unit length for a solenoid near its centre is d...

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  19. An artificial satellite with a metal surface is orbiting the earth in ...

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  20. Why the coil of a dead beat galvanometer is would on a metal frame?

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