Significant Digits

Background: Precision in measurement is how close one can measure without estimating the value. Significant figures allow recorded measurements to be all exact numbers (measured numbers) plus one uncertain number.
Purpose: To become familiar with principles of measurement, precision, and significant digits.

Procedure: Length

1.  Measure the items listed in the data table with the “Meters Only” side of the measuring stick. Estimate using only tenths of a meter. Record the length.

2.  Measure the same items using the “Meters and Decimeters” side of the measuring stick. Record answers using exact markings plus estimates to the 0.01 place.

3.  Measure the same items using the “Meters and Centimeters” side of the measuring stick. Record answers using exact markings plus estimates to the 0.001 place.

Volume

4.  Measure the items listed in the data table with the “Liters Only” side of the measuring container. Estimate using only tenths of a liter. Record the volume.

5.  Measure the same items using the “Liters and Deciliters” side of the measuring container. Record answers using exact markings plus estimates to the 0.01 place.

6.  Measure the same items using the “Liters and Centiliters” side of the measuring container. Record answers using exact markings plus estimates to the 0.001 place.

Data Table

Length / “Meters Only” / “Meters and Decimeters” / “Meters and Centimeters”
Lab desk
Ring stand
Sink width
Floor tile
Significant figures
Volume / “Liters Only” / “Liters and Deciliters” / “Liters and Centiliters”
1 pint
20 ounces
1 quart
1 gallon
Significant figures

Questions:

1.  Circle the following measurements that could be determined by a stick marked in 1/10 (decimeters) of a meter? How many significant figures are in each correct answer? 2.33 m___, 0.3456 m___, 21.67 m___, 3800.9745 m___, 1.32 m___

2.  Circle the following measurements that could be determined by a container marked in 1/100 (centiliters) of a liter? How many significant figures are in each correct answer? 2.337 L___, 0.3456 L___, 21.6789 L___, 3800.974 L___, 1.3223 L___

3.  When reading a thermometer with 1° increments, a temperature reading between 0°-1° has _____ certain number/s, ______uncertain number/s, and therefore _____ significant figure/s.

4.  When reading a thermometer with 1° increments, a temperature reading between 1°-10° has _____ certain number/s, ______uncertain number/s, and therefore _____ significant figure/s.

5.  When reading a thermometer with 1° increments, a temperature reading between 10°-100° has _____ certain number/s, ______uncertain number/s, and therefore _____ significant figure/s.