What is an Induced Electromotive Force?
- We can induce a current in the loop by changing the magnetic field. As we have discussed earlier in Faraday’s law, we have seen some experiments based on this theory.
- In the first experiment, the ammeter shows zero current reading which proves that a stationary magnet does not induce a current in a coil.
- In the second experiment, the meter shows the induction of the current which demonstrates that it is due to the change in the magnetic field as the magnet is moved towards or away from the coil.
- So it is clear that a constant magnetic field does nothing to the coil, while a changing field causes current to flow.
- Hence, we have observed from the above experiments that, only a changing magnetic field can make the current flow. To be more accurate, if the magnetic flux through a coil is changed, a voltage will be produced. This voltage is known as the induced emf.
What is Magnetic Flux?
- Magnetic flux is linked with the surface area when it is held inside the magnetic field. When the direction of the magnetic field is perpendicular to the surface area, magnetic flux on the surface is more. When the magnetic field is parallel to the surface area, the magnetic flux on the surface is less.
- The unit of magnetic flux is Weber (Wb).
Have you ever wondered that when the coil completely remains inside the magnetic field during motion, why no current flows through it?
When the coil is entirely inside the magnetic field, the two ends of the coil become positive and the other ends of the coil become negative. The potential difference of the coil will be equal in each case. So when two cells having equivalent electromotive force are connected to each other, then no current flows through the coil, and no net Induced Electromotive force exists in the coil.
Do you know what happens when the string of the electric guitar vibrates? When the string of an electric guitar vibrates, an electromotive force is introduced in the coil. The induced magnetization in the string is picked up from the vibration of the guitar. The input of an amplifier of the guitar is connected to the two ends of the coil which are connected to the speakers.
Stay tuned with BYJU’S to learn more about emf, induced electromotive force, and much more.
Frequently Asked Questions – FAQs
What is a force?
A force is usually defined as an influence that can alter the motion of a body. A force can cause a body with mass to alter its velocity.
What is a magnetic field?
A magnetic field is a field that describes the magnetic effect on moving charges, magnetic materials and electric currents.
Explain the force due to a magnetic field.
Magnetic fields can exert a force on an electric charge only if it is moving, just as a moving charge generates a magnetic field. This force increases with both an increase in charge and magnetic field strength. In fact, the force is greater when charges have higher velocities.
What is meant by magnetic flux?
Magnetic flux is the number of magnetic field lines existing on a given closed surface.
What is meant by electromotive force?
In electromagnetism, an electromotive force is an electrical force generated by a non-electrical source. It is calculated in volts.
Comments