Measurement
Tools and Readings
Determining submarkings
• Every submark on a tool is not labeled, so
you must be able to determine the quantity
it represents.
What does each of the small divisions represent below?
10
20
30
40
50
What does each of the small divisions represent below?
10
20
30
40
50
There is a magnitude difference of 10 units between each
marking. There are 10 divisions between each marking.
Therefore, each subdivision = 1 unit.
10 units
10 divisions
= 1unit/division
The general rule for determining the value of a
subdivision is:
difference between adjacent marks = # of units per division
# of divisions between adjacent marks
Try these:
10
30
50
70
90
20 units/ 10 divisions = 2 units/division
10
11
12
13
14
1 unit/ 10 divisions = .1 units/ division
1
2
3
4
1 unit / 4 divisions = .25 units/division
5
The math symbol “/ ” means
divided by.
In words, “ / “ is said “per”.
So, 3 km/hr would be said
“three kilometers per hour”.
Why is this skill important?
Determining the true value of submarkings
enables you to take accurate measurements.
Your data is then accurate.
AND
Calculations and conclusions are meaningful.
Now try these:
10
20
30
40
10 units/ 4 divisions = 2.5 units/division
50
10
50
20
30
40
10 units/ 5 divisions = 2 units/division
10
11
12
13
1 units/ 5 divisions = .2 units/division
14
Now let’s read measurements.
46 units
10
30
50
70
90
1.9 units
10
11
12
13
14
2.75 units
1
2
3
4
5
One Last Time:
26 units
10
20
30
40
50
30
40
50
9 units
10
20
2.1 units
10
11
12
13
14
Common Mistake
• Reading the inch markings are not the same
as in metric.
• There are NOT 10 divisions in each inch.
• There are 16 divisions!!
• One division = 1/16 = .0625 NOT 0.1
Read the length:
1
2
3
The length is
1 3/16 inch = 1.1875 inch.
It is NOT 1.3 inch!
inch
Tools
• Ruler/ Meter stick – length
• Graduated cylinder – volume
• Thermometer – temperature
• Balance – mass
• Stopwatch/ Ticker Tape Machine - time
Reading a balance
1. Move all the riders (sliding masses) to the left.
2. Adjust the balance so that it zeros.
3. Move heaviest rider gradually to the right,
notch by notch, until the balance dips then
back up one notch to the left.
4. Use the same procedure for the remaining
riders, going heaviest to lightest.
5. Add up all the rider values to determine mass.
Read the mass indicated below:
0
0
0
0
0.1
100
10
20
30
40
50
1
2
3
4
5
0.2
0.3
0.4
200
60 70
6
0.5
7
0.6
80
90
100
8
9
10
0.7
100 + 80 + 3 + .47 = 183.47 g
0.8
0.9 1.0 g
It is important to know how to
determine the value of a
subdivision or submarking!
difference between adjacent marks
# of divisions between adjacent marks
= # of units per division