## What does work means in physics

Work has different meaning in physics then it has in our everyday life and usage. This article is all about work and what we mean , when use term ‘work’ while studying physics. When we talk about our day to day life a person working on desktop typing is doing very less work in comparison to a person lifting and carrying heavy goods.

## Class 9 term 2 science practice test papers

Given below are the practice test papers for class 9 science term two exams. you can download and practice them. If you like them do tell us in the comment section below the post

## Use of concept of electric potential

We already know about electric field and electric potential. We also know that electrostatic field is completely characterized by vector function E(r). The electric field depicts the force exerted on other electrically charged objects by the electrically charged particle the field is surrounding. Now a question arises why do we need introduction of electric potential when we already have electric field for the description of electric force between charges.

## What is heat?

1)The mean energy transferred between the two system as a result of pure thermal interaction is called Heat.It is the transfer of energy from the higher temperature object to a lower temperature object.

2) The total amount of energy transferred as heat is conventionally written as Q for algebraic purposes. Heat released by a system into its surroundings is by convention a negative quantity (Q < 0); when a system absorbs heat from its surroundings, it is positive (Q > 0).

3) Heat is similar to work as both represent ways of transferring the energy.