Exploring Thomson's Charge to Mass Ratio: Implications for Cathode Rays

In summary, Thomson was able to measure the ratio of electric charge to mass of cathode rays by applying an electric field, magnetic field, or both in combination. He found that this ratio remained the same regardless of the material inside the tube or the composition of the cathode. This may seem contradictory since charge and mass are two different things, but the ratio is not a dimensionless number and can be compared in a similar way to other quantities such as speed or density.
  • #1
linux kid
101
0
HowStuffWorks: Atoms said:
By applying an electric field alone, a magnetic field alone, or both in combination, Thomson could measure the ratio of the electric charge to the mass of the cathode rays.
He found the same charge to mass ratio of cathode rays was seen regardless of what material was inside the tube or what the cathode was made of.

Charge and mass are two completely different things, how can you have the same ratio of the two? :uhh:
 
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  • #3
linux kid said:
Charge and mass are two completely different things, how can you have the same ratio of the two? :uhh:

the ratio is not a dimensionless number (unless you're using Natural units such as Planck units and then the measure of anything is actually a dimensionless number).

when one considers the concept of speed, it's a ratio of length to time, likewise two completely different things. or density, a ratio of mass to volume, again two completely different kinds of quantity.
 

1. What is Thomson's Charge to Mass Ratio?

Thomson's charge to mass ratio is a physical constant that represents the ratio of the electric charge of an electron to its mass. It is denoted by the symbol e/m and has a value of approximately -1.76 x 10^11 Coulombs/gram.

2. How did Thomson's experiment with cathode rays contribute to our understanding of the charge to mass ratio?

Thomson's experiment involved passing cathode rays (electrons) through magnetic and electric fields to measure their deflection. By manipulating the strength of the fields and measuring the amount of deflection, Thomson was able to calculate the charge to mass ratio of the electrons. This experiment provided evidence for the existence of subatomic particles and helped to refine our understanding of their properties.

3. What are the implications of Thomson's charge to mass ratio for the study of electricity and magnetism?

Thomson's charge to mass ratio is an important constant in the study of electricity and magnetism, as it helps to explain how electrons interact with electric and magnetic fields. It also provides a basis for understanding the behavior of charged particles in various electromagnetic phenomena, such as the Hall effect and cyclotron motion.

4. How has Thomson's charge to mass ratio impacted modern technology?

Thomson's experiment and the resulting charge to mass ratio have had a significant impact on modern technology. This constant is used in the design and operation of devices such as cathode ray tubes, particle accelerators, and mass spectrometers. It also plays a crucial role in our understanding of atomic and subatomic particles, which has led to advancements in fields such as nuclear energy and medical imaging.

5. Can Thomson's charge to mass ratio be measured with modern technology?

Yes, Thomson's charge to mass ratio can be measured with modern technology. In fact, the value of this constant has been refined through various experiments and techniques over the years. Modern devices such as mass spectrometers and particle accelerators use sophisticated methods to measure the charge to mass ratio of particles, providing more accurate results than Thomson's original experiment.

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