Normal form (Scientific notation)
Normal form (scientific notation) is a way to write very large or very small numbers in a more compact form.
It has two parts:
 A number, usually in the range 0  10, called the coefficient.
 A power of ten to multiply it by called the exponent.
Big numbers
For example the distance to the sun is about 93,000,000 miles. In scientific notation.
93,000,000 would be written 93×10^{6}
10^{6} is one million (One way to remember this is 10^{6} is one with six zeros after it.)
So the notation simply means 93 times one million.
Very small numbers too
The diameter of a human hair is about 60 millionths of a meter. Or .00005 meters.
We can write this as
50 × 10^{6}
Recall that
So
50 × 10^{6} is 50 times one millionth.
In science and engineering
In science and engineering the exponent is often made a multiple of 3.
This is because the units are often quoted that way. For example we have electric power measures in watts.
1000 watts is called a kilowatt. One million volts is called a megawatt. So the coefficient is often adjusted to
make the exponent 1000, or 1,000,000.
So using watts as an example:
50 
= 50 watts 
50 × 10^{3} 
= 50 kilowatts 
50 × 10^{6} 
= 50 megawatts 
It is done on small values too 
50 × 10^{3} 
= 50 milliwatts 
In computers and calculators
Because it is hard to write in a computer program and display in calculators, this form is often written in "E" format.
So for example
 50 × 10^{6} would be written as 50E6.
 3 × 10^{6} would be written as 3E6.
Other number topics
Scalar numbers
Counting numbers
Numbers that have factors
Special values
(C) 2011 Copyright Math Open Reference. All rights reserved
