Learning work and power in 10 common questions and the solutions. Class 11 physics revision notes for chapter 6 work, energy. Are able to define work and apply the definition to solve problems revise how draw free body diagrams to. Power, work and the waterwheel activity teachengineering. But joule is the unit of work and its also the unit of energy. Identify the lever class in each of the diagrams at the right and explain why you identified each as that lever class. Work done by the force is equal to the product of the force and the displacement of the object in the direction of force. Free pdf download of ncert solutions for class 11 physics chapter 6 work, energy and power solved by expert teachers as per ncert cbse textbook guidelines. The inverse function would be log ax bor by what power must we raise ato obtain x.
Selina icse solutions for class 10 physics chapter 2 work, energy and power. The workenergy theorem states that the work done on an object by the net. Example of work is when your exerting a greatforce in pushing an box to move it to the otherside of the room. Work, power, and energy are among the most important concepts of mechanics. Workenergy theorem work, energy and power siyavula. Power is measured in watts w and is defined by how fast work is done or. Work, energy and power key concept energy is the ability to do work, and may be obtained in many forms. For example, when a coolie travels on platform with a load on his head, work done by the coolie is zero. We have only looked at a single force acting on an object. This means that the total work done on the car after 50 m is zero. Selina concise physics class 10 icse solutions work, energy. Always use the magnitude of the force and displacement in the work equation. Calculate the work done by a 47 n force pushing a 0.
The work done during each interval is equal to the area under the force vs. May 26, 2016 work is a word that has a little bit of a different meaning in physics and today, shini is going to walk us through it. Work done between two points is independent of the path b. Physics notes class 11 chapter 6 work, energy and power 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. Work and energy questions with memograde 12 physical. When a force exerted on an object causes it to move, work is done on the object except if the force and displacement are at right angles to.
During this process, the force on the cycle due to the road is 200 n and. Class 11 physics revision notes for chapter 6 work. A worksheet made up of past exam questions about energy, work done, power and efficiency. Formula of work is wfxs f force in newton s displacement in meters. Siyavulas open physical sciences grade 12 textbook, chapter 5 on work, energy. Jul 21, 2017 selina concise physics class 10 icse solutions work, energy and power provides step by step solutions for selina concise icse solutions for class 10 physics chapter 2 work, energy and power. Mathematically, the work done on an object by a constant force constant in both magnitude.
Problem 1 a body moves through a displacement of 4 m while a force f of 12. Concepts of work, kinetic energy and potential energy are discussed. For friction, when we change the direction of the displacement the force does change direction, so the sign of the work done doesnt changes, so friction does negative work, and we do positive work against it. Work, energy and power grade 11 physics question answer. Problem 1 a body moves through a displacement of 4 m while a force f of 12 newton acts on it. And ill do another presentation on all of the things that soon. Part 1 work, power, and simple machines practice test. Physics notes class 11 chapter 6 work, energy and power. Doing work either transfers energy from one object to another or transforms it from one form to another. Sometimes more than one force acts at the same time we dealt with this in grade 11. Ncert solutions for class 11 physics chapter 6 work, energy.
Doing work either transfers energy from one object to another or transforms it. Work, energy and power gcserevision, physics, forces. Power is measured in watts w and is defined by how. Grade 12 page 1 work energy power 01 july 2014 check list make sure you. Power work done time taken and using symbols, we write this as.
If the friction constant between surface and box is 0,3. Are able to define work and apply the definition to solve problems revise how draw free body diagrams to find the components of forces can state and apply the work energy theorem. Summary notes work work is done on an object when the object moves in the same plane as the force. The students are aware of the basic terms, work, energy and power. It is the rate of work done or rate of energy transfer. We can also find the work done by the force normal and the force of gravity. A moving car, walking up stairs, lifting heavy objects. Work power energy exams and problem solutions work power energy exam1 and solutions work work power energy exam2 and solutions work power energy exam3 and solutions. Since power is the rate at which work is done, the power is also 0. Questions pertain to the analysis of motion using relationships related to work and energy, mainly energy conservation and workenergy transfer principles. If a force is applied to an object at 90o to the motion of the object then that force does no work on the object. Ncert solutions for class 11 physics chapter 6 work. The work done on the box by the gravitational force 4 2.
Most of us think of work as something we would do to. Notes for work, energy and power chapter of class 11 physics. In the world of science, work has a different meaning. After 50 m, the car moves with constant velocity so the net force is zero. Chapter 6 work, kinetic energy and potential energy.
During this process, the force on the cycle due to the. In both cases we just need to know the initial and. Grade 12 physical science p1 work, energy and power past paper question neatly compiled into one file with answers. So if you apply a force without causing an object to move, you have not done any work. The displacement is 0 and so there is no work done. Work done, energy, power and efficiency exam qus teaching. Cbse class 11 physics notes chapter 6 work energy and power. If there is only one force acting then the work it does, if any, is the net work done. Force and displacement are the two essential elements of work. On this page you can read or download life sciences march 2014 free state grade 12 human impact on the environment memo in pdf format. Figure 76 graphical representation of the work done by a constant force figure 77 work done by a nonconstant force figure 78a work. Physics notes class 11 chapter 6 work, energy and power 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. Circle the answer of the most correct choice for each of the.
By the work energy theorem, this will reduce the net work done on the object falling and therefore reduce the total change in kinetic energy. We call the work done after taking all the forces into account the net work done. Oct 05, 2014 a worksheet made up of past exam questions about energy, work done, power and efficiency. Selina concise physics class 10 icse solutions work. Define work, energy and power work is defined as product of the force and displacement of an object in the direction of force. Calculate the work done by a 47 n force pushing a pencil 0.
Siyavulas open physical sciences grade 12 textbook, chapter 5 on work, energy and power. In this lesson, we revise the definition of work as. Since power is the rate at which work is done, the power. This page shows you exercises for each topic of the lesson. Ignore the rotational effects of the wheels of the truck. Most of us think of work as something we would do to earn a paycheck. Work, energy and power tuesday february 10th reading. There is also a vector product, or cross product, which becomes relevant in chapter 11 pages. Work is the energy transfered when a force causes an object to move. Power power is the way we mearure how quickly energy is being changed. Work and energy whenever a force makes something move, work is done. Work and energy questions with memograde 12 physical science. Siyavulas open physical sciences grade 12 textbook, chapter 5 on work, energy and power covering power.
When we look at the power of a moving object, we are really looking at how fast work is happening. Life sciences march 2014 free state grade 12 human impact. Work is a word that has a little bit of a different meaning in physics and today, shini is going to walk us through it. Ncert grade 11 chapter 6, work, energy and power, is a part of unit iv, work, energy and power that holds 17 marks of weightage in combination with unit v and vi. Produced in collaboration with pbs digital studios. If power is force times velocity, and force is mass times acceleration, then what in the world do we mean by. Motion of system of particles and rigid body and gravitation respectively. For example, when a body slides over a rough surface, the work done by frictional force is negative. The definition, work is done when a force exerted on the object causes the object to move in the direction of. The amount of work done is equal to the amount of energy transferred. The work done by the forces, the power and the difference of gravitational potential energy will be involved. Example of work is when your exerting a greatforce in pushing an box to. Work power energy exams1 work and problem solutions 1. The force term equals the weight and the distance term equals the height lifted.
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