Register to reply

Reasons why the Franck Hertz experiment might fail

by sunrah
Tags: experiment, fail, franck, hertz, reasons
Share this thread:
sunrah
#1
Jun29-12, 03:55 PM
sunrah's Avatar
P: 91
We conducted the Franck Hertz experiment with mercury vapour and got intervals for the excitation potential of 5.75 and 6.40 V. I know that the intervals should be 4.9 V.
The potentials were measured using an oscilloscope at the most convenient scales.

I just can't think what may have gone wrong other than faulty tube/air in mixture (although we should still see some intervals at 4.9 V I think?) or oscilloscope needs callibrating. The apparatus was allowed to heat up a good ten minutes before we started.

What else could have affected things?
Phys.Org News Partner Science news on Phys.org
New model helps explain how provisions promote or reduce wildlife disease
Stress can make hard-working mongooses less likely to help in the future
Grammatical habits in written English reveal linguistic features of non-native speakers' languages
AbigailM
#2
Jun29-12, 05:36 PM
P: 46
Check your cables. Sometimes the solder joints to the plugs at the end of the cables break.

Check your grounding.

Glass has capacitance and can accumulate charge but any good company will usually coat their tubes will an extremely thin metallic film to dissipate it.

Because of the capacitance, don't let anyone touch the tube during the experiment.

Did you give the filament a little time to warm up?


Register to reply

Related Discussions
Franck Hertz experiment Quantum Physics 0
Franck-Hertz experiment General Physics 0
Franck-Hertz experiment Quantum Physics 0
Franck-Hertz experiment Quantum Physics 0
Franck-Hertz Experiment Introductory Physics Homework 5