The clear example of well structured academic essay. I hope it will help someone :)

1. Adel Nuralina
10th
form
The change of substance’s state matter
Antoshin Y.N.
16.03.12
Hail. Is it so dangerous?
The first mention of hail is found in the world’s ancient book – the Bible, whereit is
said: “So there was hail, and fire flashing up amidst the hail, very grievous, such as had not
been in all the land of Egypt since it became a nation.And the hail smote throughout all the
land of Egypt all that was in the field, both man and beast; and the hail smote every herb of
the field, and broke every tree of the field.” Since ancient times people have known that hail
can be considerably dangerous for an outer world. Only in the middle of the past century
physicists and meteorologists developed the theory of hail processes. Hail forms as a result of
evaporation of water in cumulonimbus cloudsand the precipitation of it canharm to
surroundings.
The amount of any liquid (gasoline, ether, water) located in an open vessel gradually
decreases. The liquid does not disappear completely and turns into steam. Evaporation of
water is the process when the water from liquid or solid state turns into gas. The mechanism
of evaporation presents the process when molecules of water overcome the force
ofintermolecular attraction and dash out forming the steam over the liquid. Evaporation rate
depends on the temperature of water. Because of this when the temperature of water is higher
it evaporates more quickly. Therefore the evaporation in summer is more intensive. The sun
evaporates water from the surface of oceans, seas, lakes and rivers. When the water steam

2. comes up, it becomes cool and turns into liquid or solid state. This process promotes the
formation of clouds.
Clouds differ in forms and sizes. The cumulonimbus clouds are the highest clouds. It
is called high because the height of these clouds corresponds to ten towers CN in Canada (the
height of each tower is five hundred and fifty three meters). The hail forms only in the
cumulonimbus clouds. Raindrops come up to the top layer of the cloud by powerful ascending
air streams and harden into little piece of ice. After that these little pieces go down tothe
warmer layer of the cloud where the water envelopes it. For example, on the altitude of eight-
ten kilometers and the temperature thirty five-forty degrees Celsius below zero the ice
particles freeze the drops and go down to lower layers of the cloud. However, wet hailstones
are moved to the high cold layers of the cloud and freeze there. At the expense of these
raisings and falls the hailstone reaches exact sizes.
The diameter of simple hailstones is nearly one centimeter. However, in individual
cases hailstone can reach even twenty centimeters. There was agrievous case when in 1961 in
Northern India chunk ice with weight three kilograms and diameter eighteen centimeters
leaded to the loss of an elephant. Different factors influence on the size of the hailstone.
Firstly, the size of hailstone depends on quantity of collisions between the germs of hailstones
and drops. If the hailstone collided with simple drops for a hundred million times, its diameter
at the average contains one centimeter. Secondly, the size of a hailstone depends on the speed
of air streams in the cloud. If the raising air streams cannot hold born hailstones, so the
hailstones fall in the form of precipitation on the ground. Most often such hailstones have
simple size. But in individual cases the speed of raising and descending streams in the cloud
can reach the speed nearly three hundred kilometers per hour. In this case hailstone can reach
large size.

3. The momentum of hailstones increases with its growth. In instance, the hailstone
which has diameter about four centimeters can reach the speed one hundred kilometers per
hour. That is why it is easy to suspect what damage can be caused by hail. Hail breaks down
vines and branches of fruit trees, bring down the fruits, destroysgrain crops, breaks down
stalks of sunflower and corn, knocks tobacco and melon plantations. Sometimes because of
hailstones’ knock domestic bird or cattle perish. In Eastern Kazakhstan on the seventh June of
2011 the hail harmed crops and caused the cattle’s perish. The hail had diameter thirteen
centimeters and harmed several rural schools, 4936 hectares of crops, and caused the perish of
four heads of livestock and seventy eight heads small cattle. In any case the hail can deal
physical or material damage.
To sum up, evaporation corresponds to the formation of cumulonimbus clouds and
after that the hail falls on the ground and harm. Unfortunately, there are only few ways of
warnings. Moreover with the help of achievements in meteorology people can find out the
probability of hail. If we know about the hail beforehand, we can save the harvest (e.g. in the
country cottage). First of all, you need to put the boards around the rows horizontally and then
put the tarp. Afterwards you need to cover the rows by thick cloth or dense cellophane. But
hail can catch people anywhere at any time. If person is in the building during the hail, he
(she) should not leave it and close all the windows. Sometimes, the person can be outside. In
this case he (she) needs to cover the head by arms and find any shelter. Observing the safety
tips, people are able to reduce a lot of losses.

4. The list of the literature:
1. Bible, exodus 9, 24-25
2. The big encyclopedia
3. OXFORD encyclopedia
4. Physics in nature
5. Article: «Град. Образование града» http://www.zooeco.com/0-jeti/0-jeti001.html
6. Article: «Испарение»http://ibrain.kz/mod/book/view.php?id=200&chapterid=641
7. Article: «Характеристика процесса испарения с водной поверхности»
http://www.pppa.ru/geology/about08/water08.php
8. Article: «Облака и облачность, высокие облака» http://bd-yacht-
club.at.ua/publ/stai/stati_i_rasskazy/oblaka_i_oblachnost/6-1-0-4
9. Article: «Сильный град в Восточном Казахстане повредил посевы и привел к
гибели скота» http://tengrinews.kz/kazakhstan_news/189898/
10. Article: «Град» http://www.somedata.ru/fertility/ground17spas/spas19.php