Sources of Energy

A good source of energy would be one with (i) A large amount of work per unit volume or mass; (ii) easily accessible; (iii) easy to store and transport; and (iv) economical.


Know more about the break up of marks and types of questions which you will face in the CBSE Science Board Examination 2018.

Electro-Magnetic Induction [ EMI ]

Induction means to create. Electromagnetic induction means to create electricity. Logically if electricity can create magnetic effect or magnetism, then by reverse analogy by using magnetism we can electricity. It’s true, first thought by Sir Michael Faraday…[…]

Electric Motor

An electric motor is a rotating device that converts electrical energy to mechanical energy. An electric motor is used as an important component in electric fans, refrigerators, mixers, washing machines, computers etc…[…]

Magnets and Magnetic Fields

A magnet is a piece of iron or other material which exhibits properties of magnetism, such as attracting other iron-containing objects or aligning itself in an external magnetic field…[…]

Electricity – Heating Effects

We all know that current heats when it passes through a wire.  We want to find out why current heats the wire and what is the amount of heat generated…[…]

Electricity – Ohm’s Law and Resistivity

The electric current flowing through a metallic wire is directly proportional to the potential difference V, across its ends provided its temperature remains the same…[…]

Electricity – An Introduction

We explore some basic questions about electricity like What constitutes electricity? How does it flow in an electric circuit? What are the factors that control or regulate the current through an electric circuit?…[…]

Scattering of Light

Scattering of Light can be thought of as the deflection of a ray of light from a straight path by irregularities or non-uniformities in the propagation medium, through which it passes…[…]

Light – Lens Formula and Power of a Lens

Lens formula is similar to Mirror formula except that the +ve sign is replaced by -ve sign.  The power of a Lens is the power on our spectacles…[…]

Refraction & Refractive Index

Refraction is an important phenomenon exhibited by light when it travel from one medium to another.  One of the ways to measure refraction is the refractive index…[…]