FranckHertz experiment and the energy levels of Hg

Franck-Hertz experiment and the energy levels of Hg Geng Xinyu Adviser: Yao Hongying 2016. 6

Objective: Energy levels of mercury(Hg) Fig 1. Energy levels of Hg Modern Physics Experiment Fig 2. Particles collision in F-H tube Franck-Hertz experiment 耿鑫宇 2

Apparatus & circuit The higher excitation levels of mercury(Hg) Fig 3. 1 Modern Physics Experiment Fig 3. 2 Franck-Hertz experiment 耿鑫宇 3

Design: Orthogonal table Table 1. Orthogonal table 1 2. 8 1. 0 2 3. 2 1. 5 3 3. 4 2. 0 Modern Physics Experiment 1 1 2 1 2 2 3 1 3 3 4 2 1 2 5 2 2 3 6 2 3 1 7 3 1 3 8 3 2 1 9 3 3 2 Franck-Hertz experiment 耿鑫宇 4

T=170℃ Modern Physics Experiment Fig 4. F-H curve Franck-Hertz experiment 耿鑫宇 5

Comments on the measure above Fig 5. Vt-Vs curve Modern Physics Experiment Franck-Hertz experiment 耿鑫宇 6

�� Calibrated with direct measure by avometer T=170℃ (After the calibration of scan voltage) Fig 6. U-n Modern Physics Experiment Franck-Hertz experiment 耿鑫宇 7

Comments on the measure above Fig 6. U-n Modern Physics Experiment Franck-Hertz experiment 耿鑫宇 8

Analysis of the F-H curve i. The peak separation increases with n 3 4 5 6 7 8 9 10 11 4. 8 V 4. 7 V 4. 8 V 4. 9 V 5. 0 V Fig 7. Residual of U Modern Physics Experiment Fig 8. Excitation cross section Franck-Hertz experiment 耿鑫宇 9

Analysis of the F-H curve ii. With the increase of the temperature of the tube 11. 4 V 11. . 3 V Fig 9. F-H curves in varied temperature Modern Physics Experiment Fig 10. F-H curves in varied Vf Franck-Hertz experiment 耿鑫宇10

Comments on the measure above 16 14 12 10 8 6 4 2 0 0 1 2 3 4 5 6 Fig 11. Measure of differential spectrum Modern Physics Experiment Franck-Hertz experiment 耿鑫宇11

�� Measure of differential spectrum Fig 12. Measure of differential spectrum Modern Physics Experiment Franck-Hertz experiment 耿鑫宇12

The higher excitation levels of mercury(Hg) 26. 6 28. 8 24. 0 21. 9 20. 1 8. 5 12 peaks in 4 groups 3. 6 15. 1 13. 7 17. 3 10. 3 Fig 13. F-H curve (Higher excitation levels of Hg) Modern Physics Experiment Franck-Hertz experiment 耿鑫宇13

The higher excitation levels of mercury(Hg) Table 2. combination of excitation levels U observed Value V Combinat ion 3. 6 calculated / / 8. 5 4. 9 a 4. 9 0. 0 10. 3 6. 7 c 6. 7 0. 0 13. 7 10. 1 a+b 10. 3 -0. 2 15. 1 11. 5 a+c 11. 6 -0. 1 17. 3 13. 7 2 c 13. 4 +0. 3 20. 1 16. 5 2 a+c 16. 5 0. 0 20. 5 16. 9 a+b+c 17. 0 -0. 1 21. 9 18. 3 a+2 c 18. 3 0. 0 24 20. 4 3 c 20. 1 +0. 3 26. 6 23 2 a+2 c 23. 2 -0. 2 Modern Physics Experiment Value V Error 26. 6 28. 8 24. 0 21. 9 20. 1 8. 5 3. 6 15. 1 13. 7 17. 3 10. 3 Fig 13. F-H curve (Higher excitation levels of Hg) Franck-Hertz experiment 耿鑫宇14

The higher excitation levels of mercury(Hg) U observed Value V Combinat ion Value V calculated Error 3. 6 / / 8. 5 4. 9 a 4. 9 0. 0 10. 3 6. 7 c 6. 7 0. 0 13. 7 10. 1 a+b 10. 3 -0. 2 15. 1 11. 5 a+c 11. 6 -0. 1 17. 3 13. 7 2 c 13. 4 +0. 3 20. 1 16. 5 2 a+c 16. 5 0. 0 20. 5 16. 9 a+b+c 17. 0 -0. 1 21. 9 18. 3 a+2 c 18. 3 0. 0 24 20. 4 3 c 20. 1 +0. 3 26. 6 23 2 a+2 c 23. 2 -0. 2 Modern Physics Experiment c= b= a= Fig 14. Higher excitation levels of mercury Franck-Hertz experiment 耿鑫宇15

Ionization energy of mercury(Hg) 12. 75 V 7. 20 V Fig 15. ionization energy of Hg Modern Physics Experiment Fig 16. I-U curves T=73℃, Vf=12. 73 V Franck-Hertz experiment 耿鑫宇16

Ionization energy of mercury(Hg) 10. 29 12. 60 7. 10 1000. 8 12. 73 12. 75 7. 20 1005. 6 15. 67 12. 85 7. 25 1010. 4 18. 28 12. 85 7. 20 1015. 6 12. 75 V 7. 20 V Fig 16. I-U curves T=73℃, Vf=12. 73 V Modern Physics Experiment Franck-Hertz experiment 耿鑫宇17

Conclusion Fig 1. Energy levels of Hg Modern Physics Experiment Franck-Hertz experiment 耿鑫宇18

Thanks! Modern Physics Experiment Franck-Hertz experiment 耿鑫宇19