# Work And Energy Class 11 Pdf Printer

## Work, Energy and Power

When a force acts on an object and the object actually moves in the direction of force, then the work is said to be done by the force. Work done by the force is equal to the product of the force and the displacement of the object in the direction of force.

If under a constant force F the object displaced through a distance s, then work done by the force. Work done by a constant force depends only on the initial and final Positions and not on the actual path followed between initial and final positions.

If under a constant force F a body is displaced through a distance s in time t, the power. Its S1 unit is watt and its dimensional formula is [ML 2 T -3 ].

Its S1 unit is joule and CGS unit is erg.

## NCERT Solutions for Class 11 Physics Chapter 6 - Work, Energy and Power

Its dimensional formula is [ML 3 T -3 ]. There are several types of energies, such as mechanical energy kinetic energy and potential energy , chemical energy, light energy, heat energy, sound energy, nuclear energy, electric energy etc.

The sum of kinetic and potential energies at any point remains constant throughout the motion. It does not depend upon time. This is known as law of conservation of mechanical energy. The energy possessed by any object by virtue of its position or configuration is called its potential energy.

## Work, Energy and Power Class 11 Notes Physics Chapter 6

Potential energy is defined only for conservative forces. It does not exist for non-conservative forces. In a non-inertial frame it can be written as:. For conservative forces the sum of kinetic and potential energies of any object remains constant throughout the motion.

## Work,Power and Energy, Chapter Notes, Class 11, Physics (IIT-JEE & AIPMT) | EduRev Notes

Collision between two or more particles is the interaction for a short interval of time in which they apply relatively strong forces on each other. In a collision physical contact of two bodies is not necessary. The collision in which both the momentum and the kinetic energy of the system remains conserved are called elastic collisions. The collision in which only the momentum remains conserved but kinetic energy does not remain conserved are called inelastic collisions.

## NCERT Solutions for Class 11 Physics Chapter 6 Work Energy and Power

If after the collision two bodies stick to each other, then the collision is said to be perfectly inelastic. The ratio of relative velocity of separation after collision to the velocity of approach before collision is called coefficient of restitution resilience.

If the initial and final velocities of colliding bodies lie along the same line, then the collision is called one dimensional or head-on collision.

When masses of two colliding bodies are equal, then after the collision, the bodies exchange their velocities. If a light body of mass m 1 collides with a very heavy body of mass m 2 at rest, then after collision.

## Sub-topics of class 11 physics chapter 6 Work, Energy and Power

It means light body will rebound with its own velocity and heavy body will continue to be at rest. If a body is dropped from a height h o and it strikes the ground with velocity v o and after inelastic collision it rebounds with velocity v 1 and rises to a height h 1 , then. If after n collisions with the ground, the body rebounds with a velocity v n and rises to a height h n then.

If the initial and final velocities of colliding bodies do not lie along the same line, then the collision is called two dimensional or oblique Collision.

## Class 11 Physics Revision Notes for Chapter 6 - Work, Energy and Power

If a particle A of mass m 1 moving along z-axis with a speed u makes an elastic collision with another stationary body B of mass m 2. April 22, Share on Facebook Share on Twitter. Work When a force acts on an object and the object actually moves in the direction of force, then the work is said to be done by the force.

Work done by a force is zero, if a body is not displaced actually, i. Work done by a force is negative if angle between F and s is obtuse angle. Gravitational force, electrostatic force, magnetic force, etc are conservative forces. All the central forces are conservative forces.

## Class 11 : Work,Power and Energy, Chapter Notes, Class 11, Physics (IIT-JEE & AIPMT) | EduRev Notes

Frictional force, viscous force, etc are non-conservative forces. It is a scalar quantity.

Mechanical Energy The sum of kinetic and potential energies at any point remains constant throughout the motion.

Mechanical energy is of two types: 1. Kinetic Energy The energy possessed by any object by virtue of its motion is called its kinetic energy.

Potential Energy The energy possessed by any object by virtue of its position or configuration is called its potential energy.

## Class 11 Physics Revision Notes for Chapter 6 - Work, Energy and Power - Free PDF Download

Potential energy depends upon frame of reference. Work-Energy Theorem Work done by a force in displacing a body is equal to change in its kinetic energy.

Mass-Energy Equivalence According to Einstein, the mass can be transformed into energy and vice — versa. Principle of Conservation of Energy The sum of all kinds of energies in an isolated system remains constant at all times.

Principle of Conservation of Mechanical Energy For conservative forces the sum of kinetic and potential energies of any object remains constant throughout the motion.

Collisions Collision between two or more particles is the interaction for a short interval of time in which they apply relatively strong forces on each other.

## Work and energy class 11 pdf printer

Elastic collision The collision in which both the momentum and the kinetic energy of the system remains conserved are called elastic collisions. In an elastic collision all the involved forces are conservative forces.

Total energy remains conserved. Inelastic collision The collision in which only the momentum remains conserved but kinetic energy does not remain conserved are called inelastic collisions.

## 8.01x - Lect 11 - Work, Kinetic & Potential Energy, Gravitation, Conservative Forces

In an inelastic collision some or all the involved forces are non-conservative forces. Total energy of the system remains conserved. Coefficient of Restitution or Resilience The ratio of relative velocity of separation after collision to the velocity of approach before collision is called coefficient of restitution resilience. It is represented by e and it depends upon the material of the collidingI bodies. Neepur Garg.