1. Problem No.1 Invent yourself
SHI Ruikang, Team China

2. Topic
Precise weighting. Study the physical effects that influence precise weighting of solid objects with a mass of 10 to 100 g.

3. Our statement
How does temperature influence the result of weighting an object with an electronic balance?

4. Outline
PART I The operating principle of electronic balance PART II Theoretical analysis PART IV Experiment PART V Conclusion PART VI References

5. I. The operating principle of electronic balance
Force balance: Gravity and Ampere’s force

6. I. The operating principle of electronic balance
Put weight on the plate Gravity increases A light barrier triggers a sensor The current in the coil increases The plate is balanced again

7. I. The operating principle of electronic balance
When the forces are balanced, an A/D converter transforms the current intensity into digital signal. Thus, the balance can show the weight of the object.

8. II. Theoretical analysis
Gravity: Ampere’s Force:

9. II. Theoretical analysis
When temperature changes: and will differ.

10. II. Theoretical analysis
Δm/g
Δ𝑇/ ℃

11. III. Experiment

13. Δm/g ℃

14. Conclusion

15. References
《电子天平温度漂移的产生及其补偿的方法》-邓志军

16. Thank you for you attention!