What is the difference between Work,Energy and Power: Class 9 CBSE - Future Study Point

What is the difference between Work,Energy and Power: Class 9 CBSE

What is the difference between Work, Energy and Power: Class 9 CBSE

What is the difference between Work, Energy and Power: Class 9 CBSE

What is the difference between Work, Energy and Power: Class 9 CBSE

What is the difference between Work, Energy, and Power Class 9 CBSE: Work is the product of force and displacement in the direction of force, energy is the efficiency of doing work and power is the rate of doing work or the rate of consumption of the energy.Here the detail of the physics terms, Work, Energy, and Power are explained beautifully so that each student could understand basic physics concepts clearly before upgrading to the higher class physics.

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  • Definition of the work
  • The formula of the work
  • Unit of work
  • Example of work
  • Definition of the Energy
  • The formula of the Energy
  • Unit of Energy
  • Example of Energy
  • Work-Energy Theorem
  • Definition of the power
  • The formula of the power
  • Unit of power
  • Example of power

Work Definition:

The work is the product of the force and displacement in the direction of the force or the component of the force,for the complete definition of work, force should be replaced by the component of the force, since force, as well as displacement both, are vector quantities the angle between force and displacement may be 0° to 90°, therefore, one component of force displaces the object in the direction of the force.

In real life the meaning of work is quite different, for example, if somebody is working on a computer then scientifically there is no work done because the computer is not displaced by the worker.

The formula of the work:

Where W is the work done and Fcosθ is the component of the force in the direction of the displacement and d is displacement.

Class 9 students of CBSE are required to remember only that

W= F×d

Unit of work:

The formula for the work is

W = F.d

The unit of the work done = Unit of the force× Unit of the displacement= Nm(Newton meter) =Joule

1NM is named 1 joule after the name of James Prescott Joule who discovered the relationship between mechanical work and heat transfer.

Example of work

A force of 50 N on an object displaces it up to the distance of 5m in the direction of the force, find the work done on the object.

Solution:F= 50 N, d = 5 m

W = F.d = 50 ×5 = 250 J

Definition of the Energy:

Energy is the efficiency or capacity of the doing work, energy has different forms, energy is neither created nor destroyed, and it can be changed from one form to another form. It can also be defined as a transfer of the work.

The formula of Energy:

There are several types of energy for example mechanical energy, chemical energy, nuclear energy, gravitational energy, etc.

Here we shall discuss the formula of mechanical energy which is of two types

Kinetic energy: Kinetic energy is the capacity to do work by a moving object

Let the mass of the object is m and its velocity is v then kinetic energy  is given by

Potential energy: Potential energy is the capacity of doing work by a stationary body due to its specific position.

Let the mass of the object is m and it is displaced to a certain height(h) from the ground of the earth then its potential energy is given by

Unit of Energy:

The unit of energy is the joule same as that of work done

Example of Energy: An object of the mass 50 gm is moving with a velocity of 10 m/s , finds its kinetic energy.

Solution: The kinetic energy of the object    is given by

Where m = 50 gm = (50/1000) kg = 0.05 kg and v = 10 m/s

Hence the kinetic energy of the object is 0.25 Joule

Work Energy Theorem: Work is the transfer of the energy,the work done is stored in the form of energy,both work done and energy are interconvertible to each other.The amount of work done depends on how much energy is supplied for doing work.

Let work done is W and energy transfer is ΔE

W = ΔE

Definition of the power:

Power is the rate of doing work or the rate of the amount of energy released or consumed. Power is measured as the extent of work done within a given time.

The formula of the power

The power (P) = Work/Time

P = W/T

Unit of power

The SI unit of the power is a watt

1 watt =1 Joul/second

Example of power

A bulb of 100 w is kept on up to the time of 5h, then how much work is done by it or energy consumed by it.

Solution:  P= W/T

T = 5h=5×60×60 = 1800s, P= 100 W

100 = W/1800

W= 180000 J

Class 9 Physics Important Notes

Average Speed and Average velocity

Three equation of Motions

Three laws of motion

The second  law of motion

Recoil velocity of the gun

The universal  law of gravitational force

Thrust and Pressure : Difference

Archimedes Principle: Complete detail

CBSE IX Class Science Sample Papers

Class 9 Chemistry Important Notes

Evoporation,Vapourization and Latent heat

How does the water kept in an earthen pot become cold during summer?

What are the factors affecting evaporation?,

What is the difference between solution,colloid and suspension?

What is the difference between element and the compound?

Atom, Molecule, and Atomicity

Determining Valency, Net Charge and Molecular Formula

Mole concept

Molar mass,molecular mass and mole concept

If energy is conserved then why do we need to save it for future generations?

Class 9 Biology Important Notes

Structure and Function of Cell : Cell Biology

Types of plant tissues : Class 9 CBSE Notes

Animal Tissues : Class 9 Science CBSE

E-books of physics,chemistry,biology ,maths and solutions of class 10 previous year’s question papers(click the link)

Class 9 Science previous years Question papers with solutions and important questions and answers

CBSE Class 9-Question paper of science 2020 with solutions

CBSE Class 9-Sample paper of science

CBSE Class 9-Unsolved question paper of science 2019

Click the link for NCERT Solutions for classes 9,10,11 and 12 of Maths & Science

NCERT Solutions and CBSE notes for Class 9,10,11 and 12 of Maths and Science

NCERT Solutions of Class 9 Science : Chapter 1 to Chapter 15

NCERT Solutions of Class 9 Maths : from chapter 1 to 15

NCERT Solutions Class 10 Science from chapter 1 to 16

NCERT Solutions of all chapters of Maths for Class 10 from Chapters 1 to 15

NEET Syllabus and its preparation

Specific notes for the preparation of 10 class CBSE board exam for achieving excellent marks

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Tips to get success in competitive exams

NCERT Solutions of class 9 science 

Chapter 1-Matter in our surroundingsChapter 9- Force and laws of motion
Chapter 2-Is matter around us pure?Chapter 10- Gravitation
Chapter3- Atoms and MoleculesChapter 11- Work and Energy
Chapter 4-Structure of the AtomChapter 12- Sound
Chapter 5-Fundamental unit of lifeChapter 13-Why do we fall ill ?
Chapter 6- TissuesChapter 14- Natural Resources
Chapter 7- Diversity in living organismChapter 15-Improvement in food resources
Chapter 8- MotionLast years question papers & sample papers




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