(ϒ в)
- .
: .
18.1 ճ
1. .
. , 400 .
2. .
. , 1 .
3. .
. ϳ 30 . ҳ .
4. , .
- . , . 10 , . 5 .
5. .
, 1 -1 10 , -0,5 +0,5 +1,5 . , , . .
6. .
. , . ϳ 30 .
7. .
450 , 500 , 550 , 600 .
8. .
. . .
9. .
, , , . ³ , .
. ..
. . .
LABORATORY WORK 70 Photoeffect
(COMPUTER VARIANT)
The aim:to study the phenomena of photoeffect.
Instrumentation and appliances: computer.
Course of the work
1. Enter the meaning of the wavelength light.
Entering is realized with a crawler. It is recommended to enter a meaning of fension equal 1 V. For the first experiment you must take a meaning a wavelength equel 400 nm.
2. Enter the meaning of the voltage.
Entering is realized with a crawler. It is recommended to enter a meaning of the tension equal 1 V.
|
|
|
3. Bring the particles into moving.
For this press the button - a start. After beginning of motion or entering of new meanings of wavelength and tensions you must wait 30 s for determination of the regimen of the particles moving. Only after this it is possible to do measurements.
4. Define the number of the particles, which could reach to anode.
For this press the button -a start- of the stopwatch. Through a window you can see a number of the particles, which can reach to anode. After 10 s count will stop, for the repeated measurement it must be pressed -an unset- and -a start-. Repeat this 5 times and define the average a number of particles.
5. Show on spots the voltage-current feature.
Do the all described above procedures for the another meanings of the tension, changing them with step 1 V from -1 V to 10 V and also for voltages -0,5 V, +0,5 V, +1,5 V. Do the graph of dependency of the number of the particles reached to anode from the tension. This curve is an analogue of the voltage-current feature of the photodiode.
6. Define the detaining voltage.
For given wavelength define the detaining voltage. It is the least in size negative voltage under which no one particle reaches anode. After entering a new meaning of the voltage do not forget to wait 30 s from determination of the mode of the particles moving.
7. Do the experiment for another lengths of the waves.
Define the detaining voltage for lengths of the waves 450 nm, 500 nm, 550 nm, 600 nm.
8. Define the value of Planks constant.
Do the graph of dependency of the detaining potential from frequency of the light. Planks constant calculate as making the charge of the electron to tangent of the angle of the slopping of made direct. The tangent of the angle of the slopping is defined as relation catets towards direct triangle.
9. Do a conclusion from made work.
Define so for dependency of the number particles reached to anode of the particles from voltage looks like real voltage-current feature. Mark also is dependency detaining voltages from wavelength linear and insofar close towards tabular received value of Planks constant.
Authors: Serpetsky B.A., the reader, candidate of physical and mathematical sciences.
Reviewer: Loskutov S.V., professor, doctor of physical and mathematical sciences.
20 71
(ϒ в)
- ; .
: .
20.1 ճ
1. , .
2. .
, - , . , 4 . , .
3. .
. ˳ .
4. .
.
5. .
, .
|
|
|
6. .
. .
. ..
. . .
