Photoelectric Effect

This equipment enables students to repeat the experiment for determining the quantum theory of radiation.
It can demonstrate that the energy of a photoelectron depends on the wavelength of impact radiation, not on its intensity.
In this experiment the photocathode is irradiated by a source of monochromatic radiation, and a voltage applied to tube will oppose the energy emitted by photoelectrons.
The voltage required to stop the current flow is proportional to the energy of photoelectron.
Plotting the voltage enabling to stop the current flow, versus the reciprocal of radiation wavelength will lead to a straight line whose slope can be used to calculate Planck’s constant.
Measuring very faint photocurrents will lead to accurate results.
Consequently the amplifier will be positioned at a distance of only few centimetres from photodiode.
This will avoid the introduction of foreign voltages and the lowest detectable photocurrent will be equal to approximately: 5 x 10-10 A.
This apparatus includes three filters that allow spectral separation.
The use of a small source of monochromatic mercury light is recommended.
A tungsten lamp can also be used although the results are not so good as those coming from monochromatic source.

TECHNICAL CHARACTERISTICS
Phototube : mounted inside the amplifier
Amplifier: it consists of a FET Op Amp input followed by a second operational amplifier driving the measuring panel ;
internal power supply units
Amplifier gain: 3 x 107
minimum current sensitivity: 5 x 1010 (spectral)
Separation ensured by the red, green and blue filters
The best results can be obtained with monochromatic sources such as mercury arc lamps and He-Ne laser
Dimensions : 9 x 171 x 10 (h) cm

MONOCHROMATIC SOURCE
The low-voltage mercury arc lamp of 7 W is a perfect source of monochromatic radiation for photoelectric effect.
It is provided with its own power supply and is mounted on a desk-type support.
It also includes another support for keeping the lamp in its position when it is used with photoelectric effect.
Its envelope is of quartz and it is provided with a shield for stray light.

Physical Structure of Matter Photoelectric Effect Manufacturer,Supplier and Photoelectric Effect Exporter in India