2. Measurement Tools and Readings

3. Determining submarkings Every submark on a tool is not labeled, so you must be able to determine the quantity it represents. 1020 30 4050 What does each of the small divisions represent below?

4. 1020 30 4050 What does each of the small divisions represent below? 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 = 1unit/division 10 divisions

5. The general rule for determining the value of a subdivision is: difference between adjacent marks = # of units per division # of divisions between adjacent marks

6. 1011 121314 1030 507090 20 units/ 10 divisions = 2 units/division 1 unit/ 10 divisions =.1 units/ division 12 345 1 unit / 4 divisions =.25 units/division Try these:

7. The math symbol “/ ” means divided by. In words, “ / “ is said “per”. So, 3 km/hr would be said “three kilometers per hour”.

8. 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.

9. 1020 304050 1020 304050 1011 121314 10 units/ 4 divisions = 2.5 units/division 10 units/ 5 divisions = 2 units/division 1 units/ 5 divisions =.2 units/division Now try these:

10. Now let’s read measurements. 46 units 1030 507090 1011 121314 12 345 1.9 units 2.75 units

11. One Last Time: 1020 304050 1020 304050 1011 121314 26 units 9 units 2.1 units

12. 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

13. Read the length: 1 2 3 inch The length is 1 3/16 inch = 1.1875 inch. It is NOT 1.3 inch!

14. Tools Ruler/ Meter stick – length Graduated cylinder – volume Thermometer – temperature Balance – mass Stopwatch/ Ticker Tape Machine - time

15. 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.

16. 0200100 010 90 504030 20 807060100 01 9 543 2 87610 00.10.9 0.5 0.4 0.30.2 0.8 0.7 0.61.0 g Read the mass indicated below: 100 + 80 + 3 +.47 = 183.47 g

17. It is important to know how to determine the value of a subdivision or submarking! difference between adjacent marks = # of units per division # of divisions between adjacent marks