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Power an Overview

Power can be defined as the amount of energy needed to be transferred or converting per unit of time. It is a scalar quantity.

In some earlier cases power is also called activity. The SI unit of power is watt. One joule can be defined as 1 joule per second. 

Power can be directly related to various different quantities like, power is required to move a ground vehicle can be defined as the product of traction force of the wheels and the velocity by which the vehicle travels. Secondly, the power which is an output product of torque generated along with the angular velocity of the vehicle, etc. 

Formula of power

Power can simply be stated as the rate in respect to time by which work is done. 

P = dW / dt

P here stands for power, with W denoting work and t is for time. 

Incase of constant force being applied as F for a distance of x then the formula to find out work done is, 

P = dW / dt = d / dt (F.x) = F. dx/dt = F. v

Inductor

An inductor is a passive two-terminal electrical component which is tasked with storing energy in a magnetic field during the flow of electric current through it. It can also be referred to as a coil, choke or reactor. Inductors were first produced in the year 1831 by Michael Faraday . It works on the principles of electromagnetic induction. 

The main component of an inductor is an insulated wire which is wound into a coil. 

The types of inductors are :-

  • Air core inductor – This inductor does not require or use any ferromagnetic material. The term air core coil means to have coils wounded on plastic, ceramic and any other nonmagnetic component so that they could have air in the windings. One of the properties of the air core inductor is that the inductance of these inductors are less than ferromagnetic inductors.
  •  Radio-frequency inductor – These types of inductors mainly cause power loss in the resonant circuits by reducing the Q factors of a circuit , this broadens the bandwidth. They are mainly similar to air core indicators but they use other techniques for minimizing losses. 
  • Ferromagnetic-core inductor – This type of inductor is also called iron core inductors . It uses ferrite which is mainly there to increase the induction. The ferromagnetic material is kept as a core which would increase the coil’s inductility . 

Inductive current 

Inductance or inductive current can be defined as the tendency to oppose a change in an electrical current passing through it. The electric current has the capability to create a magnetic field around the conductor. We known change in the magnetic field releases the electromotive force into the conductors

Firstly the term was given by Oliver Heaviside. He brought the term inductance in the year 1886. He then used a symbol of L for inductance. This was done to honour the famous physicist Henrich Lenz. The SI unit of inductance is henry (H). One Henry can be defined as the amount of inductive current which causes a voltage of one volt during a change of one ampere per second . However, Joseph Henry discovered inductance. 

Conclusion

Power can be calculated in two ways when there is constant applied force and then there is the general formula which can be used. The different types of inductors are mostly used in completely different aspects because of their properties being different . The inductive current is one of the determining factors of the result shown by the inductor.

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