# icse class 7 physics energy

Answer: Energy is the capacity of doing work. Light Energy 5. Light Energy ICSE Class-7th Concise Selina Physics Solutions Chapter-4. False. For a better understanding of this chapter, you should also see summary of … Key Features : Unlimited Practice Tests; Chapter/Topic wise division; Correct solutions at the end of each Tests State two factors on which the kinetic energy of a moving body depends. True. Question 5. We Provide Step by Step Answer of Objective, True False, Fill in the blanks,Match the following, Short/Long Answer Type of Exercise-3 Energy. (a) The mass of the body: Greater the mass of the body, greater is the potential energy of the body. (b) just in the middle For both the bodies gravity and height are same so the body with greater mass possesses greater potential energy. Answer: (i) In an electric heater, oven, geyser, toaster etc., the electrical energy changes into heat energy. What do you mean by conservation of mechanical energy? The energy of a body in a state is equal to the work done on the body to bring it to that state. ICSE SolutionsSelina ICSE SolutionsML Aggarwal Solutions. It is written as P.E. APlusTopper.com provides step by step solutions for Selina Concise ICSE Solutions for Class 7 Physics. Answer: Therefore the S.I. Heat 6. Question 12. (iii) Lighting of a torch bulb. Select a Chapter from the menu to view the specific chapter. The electricity obtained from the energy possessed by the flowing water is called the hydro-electricity. Question 21. Answer: The example to show the conversion of potential energy to kinetic energy when put in use is : A stone at a height has the potential energy due to its lifted or raised position. This can be explained as follows : P.E. unit of energy is joule (symbol J). (ii) Electrical energy to mechanical energy. (b) A ball rolling on the ground possesses, (c) The energy stored in an electric cell is, (d) When a bulb lights up on passing current, the change of energy is, (f) According to law of conservation of energy, energy changes from one form to another form, but the total energy of that system. Name the type of energy (kinetic or potential) possessed by the following : (i) A moving cricket ball. Question 23. This can be explained as follows : (ii) Electrical energy to mechanical energy. They can repeat the lessons as … or U. Give one example to show that the sum of potential energy and kinetic energy remains constant if friction is ignored. A cyclist doubles his speed. The energy of a body in motion is called its kinetic energy. Correct — One form of energy can be converted into the other form. Question 8. (g) Green plants convert light energy into chemical energy. Define the term energy. (v) A bullet fired from a gun. Two toy-cars A and B of masses 500 g and 200 g respectively are moving with the same speed. Answer: The energy is measured in the same unit as work. Question 20. ICSE Class 7 Revision Notes. State the kind/ kinds of energy possessed by the ball when it is = mgh Thus, a body may possess energy even though it is not in motion. It is the energy stored when work is done on the body to bring it to that state or position. Video Lesson. The most important use of hydro energy is to produce electricity from it. from electrical energy to mechanical energy. Answer: The examples that show the conversion of energy from one form to another are : (1) In a steam engine, the chemical energy of the coal first changes into the heat energy of the steam. This will clear students doubts about any question and improve application skills while preparing for board exams. Give one example of a body that has potential energy, in each of the following : (i) due to its position, (ii) due to its state. Matter and Its Composition 2. Question 2. i] Solution: mass m = 500 g = 0.5 kg The heat and Energy chapter deals with an intricate description of numerous perceptions under heat and energy. Answer. Which of the two has the greater kinetic energy? (v) Kinetic energy. When a cyclist doubles his speed. Watch General Effects Of Heat Energy explained in the form of a story in high quality animated videos. Actually, it is the work done on the body bringing it to the state of motion. 1800-102-5301 Login Or Join Extramarks The flowing water of river is collected in a dam at a high altitude. (iii) Light energy Answer: Free PDF download of Class 10 Physics Chapter 2 - Work, Energy and Power Revision Notes & Short Key-notes prepared by our expert Physics teachers as per CISCE guidelines. So the car with greater mass will possess greater kinetic energy. Points to Remember Work is said to be done if the applied force on the body moves it. (iv) An electric generator (or dynamo). Answer: Physical Quantities and Measurement 2. Define the term kinetic energy. (b) A ball rolling on the ground possesses, (c) The energy stored in an electric cell is, (d) When a bulb lights up on passing current, the change of energy is, (f) According to law of conservation of energy, energy changes from one form to another form, but the total energy of that system. Students who are preparing for their Class 7 exams must go through Selina Concise Physics middle school Class 7 Textbook Solutions for Chapter 4 Light Energy. His kinetic energy increases four times. (f) There is always some loss of energy in conversion from one form of energy to another form, so the total energy is not conserved. True. (ii) Chemical energy of coal changes to heat energy of the steam. Correct — A gum bottle lying on a table has energy. In short form it is written as K.E. Kinetic energy of a body is the energy possessed by it due to its motion. ... ICSE 9 Physics > Heat and Energy . The flowing water of river is collected in a dam at a high altitude. (b) Cooking gas converts chemical energy into heat energy. = mgh (iii) Potential energy. (i) Electrical energy to heat energy. (i) A moving cricket ball. Learn and practice for class VII ICSE pattern. (2) In an electric motor (or in fan), the electrical energy changes into the mechanical energy. Question 17. heat energy changes into mechanical energy. Give two examples to show the conversion of energy from one form to another. K.E. ICSE class 7 Physics Define reflected ray? In transformation of energy, the total sum of useful and non-useful energy obtained after conversion is equal to the energy converted, i.e. State the changes in form of energy while producing hydro electricity. (iv) Chemical energy = mgh . ICSE Class 7 Physics Physics is the branch of science that deals with the properties and interactions of space, time, matter and energy. The detailed, step-by-step solutions will help you understand the concepts better and clear your confusions, if any. Consider a body raised to a certain height say h. It its velocity is zero. Potential energy of a body is due to its motion, Kinetic energy of a body is due to its position or state. What was the important event in science, which took place in 1665? ... Selina Concise ICSE Solutions for Class 7 Physics Chapter 3 Energy. Answer: The toy car ‘A’ of mass ‘500 gm’ has the greater kinetic energy. Office hours: 9:00 am to 9:00 pm IST (7 days a week) Question 18. (iv) Burning of wood, coal etc. Work done by force acting on an object is equal to the magnitude of the force multiplied by the displacement of the object in the direction of the force. MCQs. Actually, it is the work done on the body bringing it to the state of motion. As the turbine rotates, it rotates the armature of the generator (or dynamo) to produce electricity. Work and Energy – Work. Then heat jenergy of steam changes into the mechanical energy which makes the train to move. Question 22. The example to show the conversion of potential energy to kinetic energy when put in use is : Answer: If no motion takes place, no work is said to be done. Work Energy Power – Notes. Physics: 1. So that you can get the best result while studying it. (ii) Potential energy of a body in the raised (or lifted) position depends on two factors : (1) the mass of the body greater the mass of the body, greater is the potential energy of the body), and (2) the height of the body above the ground (greater the height of the body, greater is its potential energy.). K.E. unit of potential energy is Joules. The potential energy of a body in the raised position depends upon the following two factors : Answer. (i) In an electric heater, oven, geyser, toaster etc., the electrical energy changes into heat energy. Visit official Website  CISCE  for detail information about ICSE Board Class-7. Answer. During the vertical fall of ball, if friction due to air is neglected, the total sum of potential energy and kinetic energy at each point of its path remains same. As the spring unwinds itself, the potential energy changes into the kinetic energy. Kinetic energy will be zero but the body will have. Question 24. This means “The total mechanical energy (P.E + K.E) of an isolated system at any instant is equal to the sum of kinetic energy and the potential energy.” It is defined as follows : Potential energy of a body is the energy possessed by it due to its state of rest or position. State any three uses of plane mirrors? True. (g) The energy of flowing water can be converted into electric energy (electricity). For both the bodies gravity and height are same so the body with greater mass possesses greater potential energy. = 1 / 2 Mv2 When v = doubles the K.E. (vi) Potential energy. When water from dam falls on the water turbine, the potential energy of the water stored in dam changes into its kinetic energy and this kinetic energy of water is transferred to the blades of turbine as the kinetic energy which rotates the turbine. A ball is made to fall freely from a height. State its unit. (ii) Potential energy. Actually, it is the work spent in bringing the body to that state of rest or position. (ii) Burning coal while operating a steam engine. Answer. Answer. Question 6. (e) One form of energy cannot be converted into another form. ICSE Sample papers free PDF for class 7 Physics has been provided by Vedantu here. Become our. Which of the two has greater potential energy ? P.E. (a) at the highest point What are the two kinds of mechanical energy. Selina Concise Physics Class 7 ICSE Solutions Chapter 3 Energy includes all the important topics with detailed explanation that aims to help students to understand the concepts better. Condition : Condition under which the mechanical energy is conserved is “when there are no frictional force.” In other words the mechanical energy is conserved strictly in vacuum where friction due to air is absent. (iv) Chemical energy to heat energy. Answer. ICSE Grade 6; Physics; Simple Machines Light . This energy rotates the axle of motor (or the blades of the fan). (iv) Electrical energy change into mechanical energy. If no motion takes place, no work is said to be done. K.E. Answer: Write true or false for each statement. The energy possessed by the flowing water is called the hydro energy. (i) Kinetic energy. Physical Qunatities & Measurement Quantities & Measurement of Volume Determination of Density Area, Speed & numericals Revision 2. Write true or false for each statement. (a) Potential energy. Work is said to be done if the applied force on the body moves it. Then heat jenergy of steam changes into the mechanical energy which makes the train to move. Selina Concise ICSE Solutions for Class 7 Physics Chapter 3 Energy • Points to Remember • Work is said to be done if the applied force on the body moves it. (a) A man going up has potential energy and kinetic energy both. Physics / Work and Energy. Return to – ICSE Class-7 Selina Physics  Solution, Sound ICSE Class-7th Concise Selina Physics Solutions, Motion ICSE Class-7th Concise Selina Physics Solutions, Physics and Mathematics HC Verma Solutions Vol-1 Class-11 Ch-2, Srijan Publications Cell Cycle and Cell division Textbook Solutions…, Introduction to Physics HC Verma Solutions Vol-1 Class-11 Physics Ch-1, OP Malhotra Linear Programming ISC Class-12 Maths Solutions Ch-28, OP Malhotra Linear Regression ISC Class-12 Maths Solutions Ch-27, OP Malhotra Application of Integrals ISC Class-12 Maths Solutions…, Privancy Policy | Sitemap | About US | Contact US, Energy ICSE Class-7th Concise Selina Physics Solutions, kinetic energy changes into potential energy, potential energy changes into kinetic energy. Here, both the cars are moving with same speed. State the changes in form of energy while producing hydro electricity. Question 13. The amount of work done depends on two factors : (i) on the magnitude of the force applied (greater the force applied, greater is the work done), and (ii) on the distance moved in the direction of force (greater the distance moved, greater is the work done). Motion 3. (v) A bullet fired from a gun. This kinetic energy does work on the nail as the stone strikes the nail arid makes the nail to move into the wood. (a) The mass of the body — Greater the mass of the body, higher is its kinetic energy. An electric eel is a fish that makes its own electricity, Lightning is spark of electricity in the air and bulb uses electricity to glow. (vii) Potential energy. Give one example to show that the sum of potential energy and kinetic energy remains constant if friction is ignored. The energy is measured in the same unit as work. As the turbine rotates, it rotates the armature of the generator (or dynamo) to produce electricity. Question 19. Selina Concise Physics Class 7 ICSE Solutions has been put together by vastly experienced teachers keeping in mind the latest ICSE syllabus and requirement of the examinations. The mechanical energy is found in two forms namely : State the condition when does it hold. What is potential energy ? (c) Kinetic energy. Two toy-cars A and B of masses 500 g and 200 g respectively are moving with the same speed.