Introduction to Torque The following picture represents the meter stick setup that can pivot at its center. One of these along with a set of weights and a hook scale will be provided to your group. 1. Draw what would happen to the board if you put a weight on one end. Try it on your own setup. 2. You have two identical 0.5 kg masses. Carefully draw where you need to place each weight on the stick so that the board stays balanced. (More than one possible correct answer) 3. Now draw the forces from each weight in your picture above. 4. You have a 0.5 kg brick and a 1 kg weight. Carefully draw where you would place each brick on the board so that the board stays balanced. (More than one possible correct answer) 5. Now draw the forces from each weight in your picture above, and use torque to explain why the board stays balanced even though the weights aren't the same. 6. Place the 1 kg mass at 20 cm to the right of the pivot. Where do you need to place the 0.5 kg mass in order to keep it from rotating? In other words...how do you keep the plank balanced or in static equilibrium? 7. Place the 0.5 kg mass at 20 cm to the right of the pivot. Where do you need to place the 1 kg mass in order to keep the plank in static equilibrium? 8. Place the 1 kg mass at 30 cm to the right of the pivot. Where should you place additional masses to achieve static equilibrium? Include the amount of mass and location in your answer. More than one answer is possible. A 9. Place the 1 kg mass at 25 cm to the right of the pivot. Make sure the plank is in static equilibrium using only 200g or less masses. Where did you place the masses? More than one answer is possible. A 10. Using evidence from the lab, describe the role the distance from the pivot plays in balancing the stick? How does this relate to what you have learned about torque? 11. What role does the mass play in balancing the plank? (Hint: Would you need to balance the plank in a "weightless" environment?) 12. Calculate the torque using T = r F for each of your forces in parts 2-9 and find the net torque on each system. Does this make sense given what you observed? 13. Now create a different set up using the scale: The 1 kg mass is located at 60 cm away from the pivot. Think about what force would need to be applied to the board to make the board be in static equilibrium. Calculate what the force should read using the equation for torque in #12. What does the scale read when the plank is in static equilibrium? 14. Add a 0.5 kg mass at 30 cm to your setup for #13. Calculate what the force should read as you did in #13. What did you measure for the force in this scenario?