Energy
Energy
Energy: The word ‘energy’ is used in many contexts, just like the word ‘work’ is. We hear people talk of a person’s energy, energy-giving tonics and drinks, solar energy, nuclear energy, energy from petrol, and so on. Energy is the ability to do work. The object which does the work, losses energy and the object on which work is done, gains energy.
The SI unit of energy is same as that of work i.e. Joule (J).
1 Joule of energy is required to do 1 J of work. Larger unit of energy is KJ.
Work done against a force is therefore stored as energy:
· When a fast moving cricket ball hit a stationary wicket, the wicket is thrown away.
· When a raised hammer falls on a nail placed on a piece of wood, it drives the nail into the wood.
Forms of energy: it exists in various forms like mechanical energy (sum of potential energy and kinetic energy), heat energy, chemical energy, electrical energy and light energy.
Mechanical Energy: The energy in a body may be by virtue of its motion(kinetic energy) or by the virtue of its position(potential energy). Energy in the body due to these conditions is called mechanical energy.
1. Kinetic energy :Energy possed by virtue of its motion is called kinetic energy. It is always positive and a scalar quantity.
2. Potential energy: It is the energy due to position. If a mass m is at a height h above a lower level, the P.E. possed by the mass is (mg)(h). There are two common forms of energy gravitational energy and elastic energy.
. Gravitational energy: When an object is allowed to fall from higher level to a lower level it gains speed duet o gravitational pull, i.e. it gains kinetic energy.
. Elastic energy: This is due to the change in the shape of the body.Some work has to be done to change the shape of the body.
Washing machine converts energy __________________ | |||
| Right Option : B | |||
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Column I shows some devices and column II shows transformation of energy for which they are used. Then match the following.
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| Right Option : B | |||||||||||||
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A steam engine converts _______________ . | |||
| Right Option : B | |||
| View Explanation | |||
Students / Parents Reviews [10]
A marvelous experience with Abhyas. I am glad to share that my ward has achieved more than enough at the Ambala ABHYAS centre. Years have passed on and more and more he has gained. May the centre flourish and develop day by day by the grace of God.
Archit Segal
7thI have spent a wonderful time in Abhyas academy. It has made my reasoning more apt, English more stronger and Maths an interesting subject for me. It has given me a habbit of self studying
Yatharthi Sharma
10thAbout Abhyas metholodology the teachers are very nice and hardworking toward students.The Centre Head Mrs Anu Sethi is also a brilliant teacher.Abhyas has taught me how to overcome problems and has always taken my doubts and suppoeted me.
Shreya Shrivastava
8thMy experience with Abhyas is very good. I have learnt many things here like vedic maths and reasoning also. Teachers here first take our doubts and then there are assignments to verify our weak points.
Shivam Rana
7thAbhyas is a complete education Institute. Here extreme care is taken by teacher with the help of regular exam. Extra classes also conducted by the institute, if the student is weak.
Om Umang
10thMy experience was very good with Abhyas academy. I am studying here from 6th class and I am satisfied by its results in my life. I improved a lot here ahead of school syllabus.
Ayan Ghosh
8thIt was good as the experience because as we had come here we had been improved in a such envirnment created here.Extra is taught which is beneficial for future.
Eshan Arora
8thAbhyas Methodology is very good. It is based on according to student and each child manages accordingly to its properly. Methodology has improved the abilities of students to shine them in future.
Manish Kumar
10thIt has a great methodology. Students here can get analysis to their test quickly.We can learn easily through PPTs and the testing methods are good. We know that where we have to practice
Barkha Arora
10thMy experience with Abhyas academy is very good. I did not think that my every subject coming here will be so strong. The main thing is that the online tests had made me learn here more things.
