1. Balancing Act Secrets of the Triple Beam Balance

2. The zero adjustment knob can be found on the far left side of the main balancing arm. If it is turned clockwise, the balance index pointer will lower. If turned counter clockwise, the index pointer will rise. The object is to turn the zero knob until the index pointer points to zero.

3. In the example shown, the index pointer is below the zero mark thus the zero adjust knob needs to be turned counter clockwise. The index is now on zero and the balance is ready to weigh an unknown.

4. STEP 1: Place the unknown in the center of the platform.

5. STEP 1: Place the unknown in the center of the platform. Notice that the index pointer is above the zero mark indicating that the amount of weight on the platform is greater than the sliding masses.

6. STEP 1: Place the unknown in the center of the platform. STEP 2: Move the 100 g sliding mass to the right until the index pointer swings below the zero mark, then back it up one notch.

7. STEP 1: Place the unknown in the center of the platform. STEP 2: Move the 100 g sliding mass to the right until the index pointer swings below the zero mark, then back it up one notch. STEP 3: Repeat with the 10 g sliding mass.

8. STEP 1: Place the unknown in the center of the platform. STEP 2: Move the 100 g sliding mass to the right until the index pointer swings below the zero mark, then back it up one notch. STEP 3: Repeat with the 10 g sliding mass. STEP 4: Slowly move the 1 g sliding mass until the index pointer lines up with the zero mark.

9. STEP 1: Place the unknown in the center of the platform. STEP 2: Move the 100 g sliding mass to the right until the index pointer swings below the zero mark, then back it up one notch. STEP 3: Repeat with the 10 g sliding mass. STEP 4: Slowly move the 1 g sliding mass until the index pointer lines up with the zero mark.

10. Add the readings of the • sliding masses for the total • mass: • g • 50 g • + 7.6 g • 157.6 g

11. 1. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

12. 2. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

13. 3. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

14. 4. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

15. 5. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

16. 6. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

17. 7. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

18. 8. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

19. 9. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

20. 10. Write the value for each sliding mass: 100 g = _______ 10 g = _______ + 1 g = Total mass: _______

21. CREDITS • All graphics taken from the following tutorial and practice activities at http://www.ohaus.com/products/education/weblab/TBBentry.html