Threshold frequency experiment

In summary, out of Sodium, Cesium, and Silver, Cesium would be best suited to coat the cathode of the light meter for sensitivity to all colors of light. This is because its work function is closest to the visible light spectrum, leaving more energy available for the maximum kinetic energy of the electrons. The calculations support this, with Cesium having the longest wavelength of 576 nanometers.
  • #1
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Homework Statement



Out of Sodium (2.75 eV), Cesium (2.14 eV) and Silver (4.73 eV), which metal would be best suited to coat the cathode of the light meter such that it is sensitive to all colors of light? The range of wavelength for visible light is 700 nm to 400 nm.

Homework Equations



threshold frequency= work function/ planks constant 4.14x10^-15
Hz= speed of light/ threshold frequency

The Attempt at a Solution



2.75/4.14x10^-15= 6.6x10^-16= 3x10^8/6.6x10^-16= 4.5 nanometers
2.14/4.14x10^-15= 5.2x10^-16= 3x10^8/5.2x10^-16= 5.8 nanometers
4.73/4.14x10^-15= 1.1x10^-15=3x10^8/1.1x10^-15= 273 nanometers

silver is the closest to being sensible to colors of light.

it seems to me like i did everything right but nothing goes to sensible light, and i don't know what I am doing wrong
 
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  • #2
For the photoelectric effect isn't it:

hf = φ + Ekmax

where φ = h*fo
and E is the kinetic energy of the electrons freed up.

So then it seems that the energy of the incident light times Plank and the frequency of the light would be your budget and the closer your work function φ is to the visible light spectra then the less that is available for the Ekmax.
 
  • #3
alright. i got the calculations now,
silver= 273 nanometers
cesium= 576 nanometers
sodium= 454 nanometers
would cesium be the most sensitive one because it emits the least frequency?
 

Related to Threshold frequency experiment

1. What is a threshold frequency experiment?

A threshold frequency experiment is a scientific experiment that involves measuring the minimum amount of energy, such as light or electricity, needed to produce a particular phenomenon or reaction. This minimum energy level is known as the threshold frequency.

2. How is a threshold frequency experiment conducted?

In a typical threshold frequency experiment, a variable frequency is applied to a sample of a substance, while the intensity of the energy is kept constant. The frequency is gradually increased until the threshold frequency is reached, and the desired response or phenomenon is observed. The threshold frequency is then recorded.

3. What factors can affect the outcome of a threshold frequency experiment?

The outcome of a threshold frequency experiment can be affected by several factors, including the intensity of the applied energy, the type and properties of the substance being studied, and the experimental conditions such as temperature and pressure. It is important to control these variables in order to obtain accurate and reliable results.

4. What is the significance of a threshold frequency experiment?

A threshold frequency experiment is important in understanding the fundamental properties of substances and their interactions with energy. It can provide valuable insights into the behavior and characteristics of materials, and has practical applications in various fields such as physics, chemistry, and materials science.

5. Can a threshold frequency experiment be used to determine the energy levels of different substances?

Yes, a threshold frequency experiment can be used to determine the energy levels of different substances. By measuring the threshold frequency, scientists can calculate the minimum amount of energy needed to cause a particular reaction or phenomenon in a substance, which can provide information about its energy levels and properties.

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