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Each prefix up or down in Table (1.2) represents an increase or decrease by power of 10.
Example 1.1
Use Table (1.1) and indicate whether the unit of each of the following measurements describes (1) length,
(2) mass, or (3) volume
________ _
A. A basket of apples is 5.7 kg.
__________ B. A bridge is 10.4 m tall.
__ _______ C. A medication pill contains 0.35 g aspirin.
__________ D. A bottle contains 1.5 L of water.
Example 1.2
Identify the measurement that has an SI unit.
1. Salem‟s height is
(A) 1.75 yd
(B) 5.8 ft
(C) 1.75 m
(D) 0.5 km
(C) 160 0F
(D) 230
(C) 34 oz
(D) 0.123 kg
(C) 1.3 hr
(D) 0.25 yr
2. The temperature is
(A) 75 0C
(B) 345 K
3. The mass of an orange is
(A) 59 lb
(B) 65 L
4. The 100m dash race was won in
(A) 10.1 s
(B) 12.7 min
1.3.2 Scientific Notation
In science, scientists use scientific notation to write very large or very small numbers. The scientific
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notation for a large number such as 56 000, 000 is 5.6 10 and for a small number such as 0.000 0005 is
5 10 7 .
A number in a scientific notation contains two parts, a coefficient and a power of 10. In the two examples
above, the 5.6 and 5 are the coefficients followed by the powers of ten respectively.
The procedure of writing a number in scientific notation consists of the following steps:
A. If the number is greater than 1
(1) Move the decimal point to the left after the first digit to give a number between 1 and 9.
(2) The spaces moved are shown as a power of ten.
(3) The power is positive