عدد عجيب 7

[Mohamad]

We know that there are 7 special facts :
- 7 days in a week
- 7 colors in rainbow
- 7 layers of heavens
- 7 continents in the world
- 7 oceans in the world
- 7 orbits in an atom
- 7 layers of the earth
MATHEMATICS
1* 7 + 3 =10
14* 7 + 2 =100
142* 7 + 6 =1000
1428* 7 + 4 =10000
14285* 7 + 5 =100000
142857* 7 + 1 =1000000
1428571* 7 + 3 =10000000
14285714* 7 + 2 =100000000
142857142* 7 + 6 =1000000000
1428571428* 7 + 4 =10000000000

BIOLOGY
Most Mammals’ neck has 7 bones.
The no. of opening into the human’s head is :
mouth , 2 eyes , 2 ears , 2 nostrils .
CHEMISTRY
The most abundant gas on earth,
NITROGEN, has atomic No. 7
There are 7 Rows in the periodic table
The HALOGEN are found in group 7
The PH of pure water is 7

PHYSICS
There are 7st Base units:
Meter, Kilogram, Second, Kelvin, Mole and Candela
There are 7 colors in the visible light:
red, yellow, green, blue, indigo, violet
The atmosphere consists of 7layers:
Troposphere, Stratosphere, Ozonosphere, Mesosphere, Thermosphere, Ionosphere, Exosphere
ASTRONOMY
There are 7 visible ( to the naked eye ) STELLER OBJICTS:
Sun, Moon, Mercury, Mars, Jupitar, Venus, and Saturn