Reversible changes in Daily Life
Reversible changes in Daily Life
Relevance of Reversible Changes in Daily Life:
1. Working of Blacksmith: A blacksmith changes a piece of iron into different tools. For that, a piece of iron is heated to red hot. This also softens it. It is then beaten into the desired shape. It is a reversible change.
2. Expansion and contraction of metals: Metals expand on heating and contract on cooling. This expansion and contraction of a metal is a reversible change.Small gaps are left between the rails that form the parallel lines of a railway track. These gaps are called expansion gaps. These gaps allow the rails expand in hot weather. If there are no gaps or gaps are too small the lines can bend.
3. Fixing wooden handles on tools: While making agricultural tools the metal ring is heated before fixing the wooden handle. On heating the metal ring expands. When the ring become bigger size the wooden handle fix easily. When the metal ring cools, it contract and the handle fits in tightly.
4. Fixing metallic rim on a wooden wheel: The fixing of metallic rim to the wooden base of the wheel of bullock cart can be done in the similar manner. The metallic rim used is slightly smaller in diameter than the wheels .On heating the rim expands. And can easily lie on the wheels. When the rim cools, it contract and press tightly on to the wheels.
Note:
Burning of a candle is a chemical change whereas melting of wax is a physical change. When wax melts, it flows down and solidifies again. So, it is a reversible and temporary change. Thus, melting of wax is a physical change. On burning a candle, wax burns to produce wax vapour and carbon dioxide. It produces heat and light and candle becomes smaller on burning. New substances are formed energy is released during the burning of candle. It cannot reversed and it is a permanent change. Thus, burning of candle is a chemical change.
Metals expand on heating and contract on cooling, it is a _______________ change. | |||
| Right Option : A | |||
| View Explanation | |||
Which of the following are correct : (a) A piece of iron is heated to red hot which softens it and it is then beaten into the desired shape. It is a reversible change. (b) Burning of a candle is a chemical change whereas melting of wax is a physical change. (c) A piece of iron is heated to red hot which softens it and it is then beaten into the desired shape. It is a irreversible change. | |||
| Right Option : A | |||
| View Explanation | |||
Which of the following shows reversible change ? | |||
| Right Option : C | |||
| View Explanation | |||
Students / Parents Reviews [20]
My 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.
Hiya Gupta
8thUsually we see institutes offering objective based learning which usually causes a lag behind in subjective examinations which is the pattern followed by schools. I think it is really a work of planning to make us students grab the advantages of modes of examination, Objective Subjective and Onli...
Anika Saxena
8thA 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
7thAbhyas is an institute of high repute. Yogansh has taken admission last year. It creates abilities in child to prepare for competitive exams. Students are motivated by living prizes on basis of performance in Abhyas exams. He is satisfied with institute.
Yogansh Nyasi
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
10thI 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
10thThird consective year,my ward is in Abhyas with nice experience of admin and transport support.Educational standard of the institute recumbent at satisfactory level. One thing would live to bring in notice that last year study books was distributed after half of the session was over,though study ...
Ayan Ghosh
8thIn terms of methodology I want to say that institute provides expert guidence and results oriented monitering supplements by requsite study material along with regular tests which help the students to improve their education skills.The techniques of providing education helps the students to asses...
Aman Kumar Shrivastava
10thWe started with lot of hope that Abhyas will help in better understnding of complex topics of highers classes. we are not disappointed with the progress our child has made after attending Abhyas. Though need to mention that we expected a lot more. On a scale of 1-10, we would give may be 7.
Manya
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 institute is one of the best coaching institute in the vicinity of Ambala Cantt area. The teachers of the institute are well experienced and very helpful in solving the problems of the students.The good thing of the institute is that it is providing extra classes for the students who are w...
Aman Kumar Shrivastava
10thMy experience with Abhyas academy is very nice or it can be said wonderful. I have been studying here from seven class. I have been completing my journey of three years. I am tinking that I should join Abhyas Academy in tenth class as I am seeing much improvement in Maths and English
Hridey Preet
9thAbhyas 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 was a good experience with Abhyas Academy. I even faced problems in starting but slowly and steadily overcomed. Especially reasoning classes helped me a lot.
Cheshta
10thMy experience with Abhyas Academy has been very good. When I was not in Abhyas whenever teacher ask questions I could not speak it confidently but when I came in Abhyas, my speaking skills developed and now I am the first one to give the answer of teachers question.
Upmanyu Sharma
7thAbhyas institute is one of the best coaching institute in the vicinity of Ambala cantt.The institute provides good and quality education to the students.The teachers are well experienced and are very helpful in solving the problems. The major advantages of the institute is extra classes for weak...
Shreya Shrivastava
8thIt 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
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
7thWhen I have not joined Abhyas Academy, my skills of solving maths problems were not clear. But, after joining it, my skills have been developed and my concepts of science and SST are very well. I also came to know about other subjects such as vedic maths and reasoning.
