Solar Energy: The earth receives a huge amount of energy from the sun. Each square metre of the earth's uprut atmosphere receives about 1.36 kilojoules (kJ) of solar energy per second. In other words, so energy is incident at the rate of 1.36 kW/m2.
The entire energy incident on the upper atmosphere of the earth does not reach its surface. About 40% of this energy is reflected by the atmosphere into space. Then some of it is absorbed by the gases and particles present in the atmosphere. Finailly, only about 47% of the incident energy reaches the earth's surface. Solar energy sustains life processes on the earth. Plants use it to make food. Traditionally we have been using solar energy for drying clothes and grains, making salt from sea water, etc. Newer uses include solar heating devices and solar cells. Solar heating devices such as solar cookers and solar water heaters use the heat energy that comes with sunlight. Solar cells convert solar energy into electricity.
Advantages Of Solar Energy: The advantages are as follows
(a) It is available everywhere.
(b) It is available in plenty (renewable), and it is free.
(c) It does not cause pollution.
Limitations of solar energy : The limitations are as follows
(a) It cannot be used at night.
(b) Devices based on solar energy do not work well on cloudy days.
Solar Heating Devices: A solar heating device uses solar energy to heat things like water and food. To make a solar heating device effective, we have to ensure that the device absorbs a lot of heat from sunlight and does not lose too much of the collected heat. To achieve these, the following measures are taken. Increasing the absorption of heat Everything on which sunlight falls absorbs heat from it. However, black and dark-coloured surfaces absorb heat better than do light-coloured and white surfaces. That is why you feel hotter than usual when you wear dark clothes in summer. In certain types of solar heating devices, the surfaces meant for collecting sunlight are painted black to increase the absorption of heat.
Reducing the loss of heat: A hot object loses heat to it surroundings by conduction, convection and radiation. Different methods are used to reduce the loss of heat in heating devices. In a box-type device, to reduce heat loss by conduction, the walls are made of an insulator, ie, a material that is a poor conductor of heat. The box is made airtight so that the air inside cannot take the heat out of the box. Thus, convection loss is also reduced. Radiation loss is reduced by covering the top of the box with giass. Sunlight passes through the glass and heats the materials inside the box. The heated materials radiate heat, but these get reflected back into the box by the glass. This traps the heat (in the same way it is trapped in a greenhouse).
Increasing the amount of sunlight collected: A reflector such as a plane mirror is used to reflect sunlight into the heating device so that more sunlight enters it
A reflector such as a _________________ mirror is used to reflect sunlight into the heating device so that more sunlight enters the device. | |||
Right Option : A | |||
View Explanation |
Which of the following gases are responsible for the Green House effect? | |||
Right Option : C | |||
View Explanation |
The radiation present in the sunlight lying beyond violet radiation is called | |||
Right Option : C | |||
View Explanation |
Abhyas 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.
In 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...
The experience was nice. I studied here for three years and saw a tremendous change in myself. I started liking subjects like English and SST which earlier I ran from. Extra knowledge gave me confidence to overcome competitive exams. One of the best institutes for secondary education.
My 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
I 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
Abhyas 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...
My 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.
We 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.
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.
My 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.
One of the best institutes to develope a child interest in studies.Provides SST and English knowledge also unlike other institutes. Teachers are co operative and friendly online tests andPPT develope practical knowledge also.
Being a parent, I saw my daughter improvement in her studies by seeing a good result in all day to day compititive exam TMO, NSO, IEO etc and as well as studies. I have got a fruitful result from my daughter.
It 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.
My 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.
When 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.
Third 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 ...
It 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.
Abhyas 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.
Abhyas 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.
Abhyas academy is great place to learn. I have learnt a lot here they have finished my fear of not answering.It has created a habit of self studying in me.The teachers here are very supportive and helpful. Earlier my maths and science was good but now it has been much better than before.