Pre-Engineering
Physics 
Chapter
1
Measurement/Precision/Significant
Figures Lab Name:_____________________________________ Other group
members:____________________________________________________________
Objective: Using a variety of measuring instruments,
with different degrees of precision, take measurements. From this data, make judgments about the
precision of these measurements.
Background: Precision (of a measuring
instrument)-refers to the smallest division on the measuring instrument. Also refers to a degree of certainty. To determine the precision of a measuring
instrument/tool, look at the instrument and read what value the smallest
division is worth, i.e. 1/16 inch, 0.01g, or 0.001 inch. Count the divisions between two successive
whole values. For example, if there are
eight divisions between 2 successive whole numbers on a yard stick, the
precision is 1/8 inch.
Problem: With the supplied measuring instruments and
objects, make the appropriate measurements and record them in the data table
below. Be sure to note the precision of
your measuring tool. (This is the
smallest division that can be measured with certainty.)
I. Linear
measurements
Measuring
tools-plastic ruler, metal ruler (4 sides), yard stick, protractor, compass, dial
caliper
Objects-thickness
of textbook, thickness of calculator
II.
Mass measurements
Measuring
tools-250g, 500g, 1000g spring scales (at eye level check for zero; adjust with
white screw at top)
Objects-one
brass mass hanging on hanger, two brass masses hanging on hanger
Data
Table: (always label units on measurements—do not reduce fractions here)
|
Measuring Tool |
Precision |
Thickness of
textbook
|
Thickness of
calculator
|
|
Plastic
Ruler English |
|
|
|
|
Yard
stick English |
|
|
|
|
Compass
English |
|
|
|
|
Caliper
English |
|
|
|
|
Protractor
English |
|
|
|
|
Measuring Tool |
Precision |
Mass of 1 weight
+ hanger
|
Mass of 2
weights + hanger
|
|
250g
spring scale metric |
|
|
|
|
500g
spring scale metric |
|
|
|
|
1000g
spring scale metric |
|
|
|
|
Triple
Beam Balance metric |
|
|
|
Questions
1. Which is the most precise linear measurement
tool?
2. Which is the least precise linear measurement
tool?
3. Which is the most precise mass measurement tool?
4. Which is the least precise mass measurement
tool?