When exams are round the corner then it is not possible to revise complete books so we have come up with unit wise formulae and important terms. Once you have gone through chapters thoroughly and understood it well there is no need to study it again and again. You can only revise important formulas and terms which will save your precious time.

In this regard find Magnetism, Electromagnetic Induction and Alternating Current's important Formulae for Quick Revision. These formulae will be helpful in various engineering entrance examinations such as IIT JEE, UPSEE, WBJEE etc.

In UPSEE and WBJEE where most of questions are asked directly on formulae, this quick revision note will be very important.

When a charge moves in an electric field it experiences a force. This is called electric force. A moving charge also experiences force when it passes through magnetic field this is called Lorentz force.

Biot Savart law gives the the formula to find magnitude of magnetic field due to incremental current element.

Using Biot Savart Law we can find the magnetic field at particular places of the regular figure. Above we used Biot Savart Law to find the magnetic field at the centre of a ring.

**UPSEE 2017 Solved Sample Paper Set-1**

Ampere circuital law is a very important concept in magnetism. Many questions are asked on the basis of this rule.

**JEE Main Mathematics Solved Sample Paper Set-VII**

If a rod of length l move in a magnetic field of magnitude B with a velocity v, thenthe emf induced can be given as:

Frequent questions are asked on combination of inductors. There are two types of possible combinations- Series Combination and Parallel Combination.

**JEE Main Physics Solved Sample Paper Set-VII**

The circuit behaves in different way when ac votltages are applied.

Phasor diagram is an important topic in altenating current. From phasor diagram we see the actual behaviour of the circuit under sinusoidal voltage.