CHAPTER 5 ■ NUMBERS AND UNITSA larger multiplier can be used, in which case the original number slides below the decimal point:10,000,000 = 0.01 billion = 0.01 giga = 0.01 G
In each case, the actual value remained the same:10,000,000 = 0.01 G = 10 M = 10,000 k
Usually the entire number is written out only if it helps make a point: “Install a 10,000,000-ohm resistor,
not 10,000 ohm!”
Not only can the powers-of-a-thousand system reduce the number of digits, but also it can group parts
together. 1200000, 32000, 13200 becomes 1.2 M, 32 k, and 13.2 k. This makes it easier to see that the last two
components are similar because they both are in the “k” range.
Don’t worry if this system seems confusing at first. It won’t take long for you to pick it up.
M & m
There are two letter “m”s used as abbreviations. The million abbreviation is uppercase “M” (see Figure 5-2),
the thousandths abbreviation is lowercase “m”.
Figure 5-2. One million represented by 1 M
Be careful not to mix these up, because there’s a huge difference in values:1 M = 1,000,000,000 m
A sales representative sent me an e-mail asking how much power a specific wireless device transmitted
through the antenna. I replied with an e-mail stating “600 mW” (that’s 0.6 watts; one-hundredth of an
ordinary 60-watt light bulb).
After a bit, it occurred to me there might be a miscommunication. I called the sales representative and
asked what she told the customer, she replied “600 megawatts.” Wow, that’s ten million light bulbs.