1. MEASUREMENT IN SCIENCE Making our efforts worthwhile

2. Why Measure? A key element of science is EXPERIMENTS When experimenting, our data is collected through MEASUREMENTS If the measurements are no good, why bother experimenting at all?

3. Using tools properly! What would you record for the length of the blue line? (ruler is in cm)

4. Estimating the last digit When making measurements, you ALWAYS estimate the last digit of the measurement. If the measurement of the volume of a container is halfway between 1 L and 2 L, you don’t round it! You write 1.5 L If it was barely over 1 L, say maybe 1/10 the way to 2 L, you write 1.1 L – ESTIMATE!

5. Try it again The balance measures mass (g) 200+60+(front beam reading) What should it be?

6. Graduated Cylinders Graduated cylinders measure volume. They have a specific issue however What is happening with the liquid? Where do we measure it?

7. The curve is called the MENISCUS. Water is attracted to the sides of the cylinder and are pulled up. The TRUE value is at the BOTTOM of the mensicus

8. Accuracy and precision Accuracy = your measurement is close to an accepted or expected value Precision = each of your measurements are very close to all other measurements It is possible to be precise without being accurate, or to be accurate without being precise!

9. The target analogy Bullseye = our accepted value Have we been accurate? How about precise?

10. In this case, have we been accurate? How about precise? Which would be more important? Why do you think so?

11. Well which outcome below would you be most impressed with?

12. ALL bull's-eyes, ALL the time! That should be the goal!