Transcript Teachers Laboratory - HST

Teachers Laboratory
Working Group
And the members are:
Tat Leong Lee
Charles Merriam
Avraam Popadopoulos
Florin Serbu
Ole Tennvassas
Aristides Tsirimiagos
Tasks / Goals
• Conduct The Six Existing Experiments
• Produce formal Lab Procedure for both
set-up and conduct of the experiments
• Operational Testing of Video
Conferencing Capability
• Brainstorm Lab arrangement and
equipment
• Investigate additional Labs
Doing The Labs
• Aristides & Florin:
– Oscilloscope and e/m apparatus
• Charles & Ole:
– Photoelectric Effect and Millikan Oil Drop
• Avraam & Tat Leong:
– Electron Diffraction and Electron Spin
Cathode Ray (Braun’s)
Tube
Cathode Ray Tube
Power supply
• CRT- Electron accelerator
• Braun-Thomson-1897
• Deflection by electrical and
(or) magnetic field
• Demonstration experiment
Magnetic Coils
Supply
Operation Unit
Determination of the Specific Charge of
the Electron
Purpose:
•Study Cathode rays.
•Study Lorentz force.
•Study of the deflection of electrons in a
magnetic field into a circular orbit.
•Determination of the magnetic field B
as a function of the acceleration
potential U.
•Determination of the specific charge of
the electron.
e
A s
 1.76  1011
me
kg
e
2 U

me ( r  k  I ) 2
Photoelectric effect
Purpose is to:
•Verify the photoelectric effect.
•Do measurements that enables us to calculate the kinetic energy of the
electrons as a function of the frequency of the light.
•Calculate Planck’s constant h from these results
•Show that the kinetic energy of the electrons is independent of the intensity of
the light.
Millikan’s Oil Drop
“Our Achilles Heel”
(1/2)
• Primary Problem focused on providing
the actual Oil Drop:
– How much oil, how many “squeezes” and
connections
• Need three hands to do the lab:
– Squeeze, hold down & operate the polarity switch
& stop watch--all while looking through eye piece:
• Recommendations: eyepiece, Video
camera and longer tube.
Phywe Millikan Apparatus
(2/2)
Electron Diffraction
(1/2)
Electron Diffraction
(2/2)
• Determine the interplanar spacing of
graphite using de Broglie relation and
Bragg’s reflection
• Related topics and concepts
– Wave-particle duality (X-ray vs. electron)
– Bragg’s reflection
– Study small structure (inaccessible to
optical)
Electron Spin Resonance
(1/2)
Electron Spin Resonance
(2/2)
• Model of electron spin resonance demonstrating the
interaction between the magnetic moment of the
electron spin with a superimposed direct or
alternating magnetic field
• Related topics and concepts
– Larmor precession
– Revise resonance, gyroscope (not main focus)
• Caveat
– No classical equivalent to spin concept!
– This is just to help student form some mental model
It is now time for a
Video
Conference
Video Conferencing
YOU have
Just
Witnessed a
Successful
Operational Test
Teacher’s Lab Requirements
• New shorter tables
• Storage:
–Re-allocate existing Cabinets
and/or
–Build New Storage
• New Power Supply Lines
Galant
Dimensions du produit
Longueur: 160 cm
Largeur: 80 cm
Hauteur: 72 cm
Epaisseur: 2 cm
Or…
Longueur: 120 cm
Largeur: 60 cm
Hauteur: 72 cm
Epaisseur: 2 cm
CHF165 - 211
Jonas
IKEA SWISS
(1/2)
Jules
Dimensions du produit
Largeur: 56 cm
Profondeur: 56 cm
Larg. assise: 44 cm
Prof. assise: 42 cm
Haut. assise min.: 41 cm
Haut. assise max.: 53 cm
CHF 69:00
Dimensions du
produit
Largeur: 41 cm
Profondeur: 51 cm
Hauteur: 63 cm
CHF 79.00
Ikea Furniture Cost estimate
Articles
Galant
tabels
Jules
chairs
Jonas
Nr
6
Price/art Price
200
1200
10
79
790
6
69
Total
414
SF 2404
(2/2)
New Lab Recommendations
• Franck Hertz (Neon) Apparatus
• Deflection of beta-particles in magnetic
field – relativistic speed
• Atomic Spectra
Franck Hertz
Deflection of  - particles in
magnetic field – relativistic speed
Equipment av ailable at ŅKPT Naturf agÓ, Norway (http://kptnaturf ag.no/shop/Fy sikk/c
at224)
Two Electron Spectra
w/Prism Spectrometer
Hg, Cd and Zn Sprectra
Γεια σας (Yia sas)
Takk for oppmerksomheten!
Multumim pentru atentie
結束，
謝謝 (Jie Shu, Xie Xie)
“That’s all Folks”