The sun as a source of energy

Solar energy(energy got from the sun) is a very useful form of energy like atomic and wind energy.The problems of rising costs of fuels like oil and gas and the pollution(dirtiness of the atmosphere) caused by them have made scientists work on solar energy for man's future use.About half of the solar energy is light,about half is infrared radiation(heat,energy,etc. in rays) and very little ultraviolet radiation.

In modern times, the first main use of solar energy is to change it into thermal energy(of heat as that of coal or gas). Solar rays hit a flat plate collector which absorbs a lot of heat.This flat plate collector is then used for water heating,house heating,air-conditioning and for getting salt from salt water and pure drinking water from sea water.Solar water-heaters are in use in Australia,Japan and America.In air-conditioning the flat plate collector supplies heat to operate an air-conditioner.In solar evaporation,saltish water is made to evaporate from ponds,and thus salt is got.In solar distillation,pure water vapor is collected in storage tanks.

Secondly,scientists are trying to convert(change)solar energy to electrical energy through solar cells.A solar cell is an invention that directly changes solar radiation to electric energy.Spaceships get their electric power through solar cells.Further,they are being used to provide power to radios,telephones, and other wireless equipment.Lighthouses at sea get their power supplies from them.At present,the cost of producing electricity from solar cells is very high.

Thirdly,heat engines are being used to convert solar energy to mechanical energy.This mechanical energy is used directly or again converted to electric energy for operating machines.Heat collectors are used to heat fluids whose steam passes through engines where it is converted to mechanical energy.

Fourthly,we can use the solar energy or heat stored in the sea.Most of the solar energy that comes to the world is taken by the sea.The water at the surface of the sea is warmer than at the depth.Heat flows from the area of higher temperature to that of a lower one.So if we make this heat of the warm water flow through a heat engine,the heat energy can be converted to mechanical or electric energy.Power plants can thus use thermal energy especially is warm waters.

Fifthly, in Japan and some other countries small plants grow in the sea by absorbing sunlight.These plants are dried and then used as food.

There have been attempts to make solar cars in Europe and elsewhere.These cars run on electric energy instead of oil.The car batteries charged with solar energy provide the electric energy.However,at present the batteries are too heavy and are charged over long hours.

Solar energy may be the answer to many of our energy problems.

The adjective or determiner

An adjective or determiner is a word used to describe or qualify or add to the meaning of a noun or pronoun.

• loud cry,weak performance.The gift was a suitable.Loud,weak,suitable are adjectives qualifying the nouns "cry,""performance" and "gift".

THE MAIN KINDS OF ADJECTIVES

1.Adjectives of qualify or descriptive adjectives
Adjectives of quality show the quality of a person or thing,and can be formed from proper nouns too:

• big,small,wise,foolish,philosophical,dangerous,peaceful and proper adjectives like the ones discussed at length below:
• American,French,Italian,Greek,Spanish,Russian,Norwegian,Indian,Chinese,Japanese,Korean,Brazilian,Australian,Egyptian,Sudanese,Ethiopian,Jordanian,Arabian,Iranian,Afghan,Turkish and Chechen and many other national groups do we find all around,but the best group stands out as the one own nation.

All the italicized words above are adjectives of quality.Pakistani,American,etc.result from the proper nouns,Pakistan,America,etc.,and they can rightly be termed Proper Adjectives.
Also note:She is an excellent singer.You are,of course,able and efficient.I can't say how fast I am at bowling.We all like Pakistanis products.The Islamic world surely needs unity.
2.Adjectives of quantity
Adjectives show the quantity of a thing or nature of quantity:

little,some,much,enough,all,no,great,half,two-third,whole,sufficient

A litle pur water,the tremendous weight of the truck,all the food,the bag full of rice,was it half full?Enough salary,great strength,insufficient food supplies,much indecency.Note:Great care is to be taken in carrying the heavy glass cause upstairs.Where did you leave your light purse,Madam?Slight pressure,weighty arguments,some love is all that is needed to win the heart of a maiden.
3.Adjectives of number
Adjectives of number indicate number or order and are also called limiting adjectives.

one,two,first,second,etc.,few,many,some,most,several,all,no,certain,each,every,either,neither,enough.

They played five matches,the first in Lahore and the last in Rawalpindi.
Some glorious efforts and a few mistakes were observable in all their efforts.
Almost all the spectators appreciated the game of our team.
Many terrorists,arrested outside the stadium yesterday,aimed to attack the people inside from several directions.
4.Demonstrative adjectives
Demonstrative adjectives point out(bring to notice) things or persons.

this,that,these ,those,such,the"same,""the "other,"yonder(over there.at some distance)

Those flowers are dear to us as much as this picture is to you.
Such objects as are related to the world of art cannot be compared with Nature.Can they?
5.Interrogative adjectives
Interrogative adjectives are question words functioning as adjectives like what,which and whose

what,which,whose

What foods do you like?("what" being general in application)
Which of the foods available here is appealing to you?("which" being particular in reference)

Proper adjectives

A proper adjective comes out of a proper noun and is descriptive of it.

To form many proper adjectives,we add a suffix such as "-n,-an,-ian,-ic, or -i" to the proper noun.

Three degrees of the adjective

An adjective has three degrees of comparison.
1.The positive degree
The positive degree shows the simple quality of an adjective.

high,great,slow,thin,beautiful,sorrowful

2.The comparative degree
The comparative degree shows a higher or lower quality of an adjective.

greater,slower,thinner,more beautiful,less high,less great,less slow,less thin,less beautiful

3.The superlative degree
The superlative degree shows the highest or lowest degree of the quality of an adjective.

highest,greatest,slowest,thinnest,most beautiful,least high,least great,least beautiful.