Spark suppression, Physics

Assignment Help:

Spark suppression:

If we consider a circuit with a large inductance, possibly one using a magnetic relay. At the instant the switch is opened, the current through the coil is changing at maximum rate, therefore the back emf induced in the coil is also at maximum.

This emf is applied to the air gap between the switch contacts and ionises the air, producing a spark which the burns the contacts. This increases their electrical resistance and radiates energy which may cause interference, therefore sparks must be suppressed. Good design of switch contacts can help, but connecting a capacitor in parallel with the switch is the best method of eliminating sparking.

When using a capacitor the energy released by the coil charges the capacitor instead of ionising air. When the switch is closed again the capacitor discharges.


Related Discussions:- Spark suppression

Which one of the subsequent is true of electric potential, Question: W...

Question: Which one of the subsequent is true of electric potential but isn't true of an electric field? Answer: The electric field acquaintances a vector with empt

State any three laws of photo electric emission, Q. State any three laws of...

Q. State any three laws of photo electric emission? (i) For a specified photo sensitive material there is a minimum frequency called the threshold frequency below which emissio

Physics Problem, Two boxes are in contact on a flat table. A force of 75.8 ...

Two boxes are in contact on a flat table. A force of 75.8 N is applied horizontally to the first box, which in turn pushes horizontally against the second box. The mass of the firs

What is equipotential surface, What is Equipotential Surface Equipoten...

What is Equipotential Surface Equipotential Surface - surface of constant potential.  No work is required in moving charges with such a surface. Electric fields are perpend

What is the initial velocity of an emitted photoelectron, The stopping pote...

The stopping potential of a photocell is 2.3 V. What is the initial velocity of an emitted photoelectron that is brought to a stop by the photocell?

Illustrate a labelled diagram of hertz experimental, Illustrate a labelled ...

Illustrate a labelled diagram of Hertz's experimental set-up to produce electromagnetic waves. Describe the generation of- electromagnetic waves using this set-up.

Explain scattered electrons made strong diffraction pattern, Davisson and G...

Davisson and Germer scattered electrons from a crystal of nickel.  The scattered electrons formed a strong diffraction pattern. What important conclusion was drawn from this experi

Gravitety, why fall an apple from a tree

why fall an apple from a tree

Magnetic field and electric current., the magnetic field at a dictance of 2...

the magnetic field at a dictance of 2cm from the axis of a straight conductor carrying current is 12mT.Find the currentin the conductor?

Schrodinger Equation, For what purpose do we use Schrodinger equation in ou...

For what purpose do we use Schrodinger equation in our daily life?

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd