The exponent can be negative or positive. A positive exponent results in a large absolute value, while a negative exponent results in a small absolute value. The speed of light has a large positive exponent while the mass of the hydrogen atom has a small negative exponent. The sign of the exponent is independent of the sign of the entire number.

Negative exponents do not affect the sign of the entire number, whether it is positive or not. Rather, they affect how close to 0 number is. Numbers with negative exponents are very close to 0, whether they are on the right or the left side of 0 on the real number line as shown in Fig. 21.1.2. The negative numbers are mirror images of the positives in this regard. -1.0x10¹ is much further away from 0, to the left, than 1.0×10^-1.