Cathode Rays and Electron Properties

According to the document, the Greek word 'a-tomio' is the origin of the word 'atom'. What does 'a-tomio' mean?

• Small particle

• Fundamental unit

• Uncutable or non-divisible

• Building block

According to his theory, what are all matter composed of?

• Electrons, protons, and neutrons

• Complex, divisible structures

• Extremely small, structureless, hard spherical particles called atoms

• Radioactive substances

J.J. Thomson discovered the electron during studies involving the passage of electricity through gases at extremely low pressures. What were these experiments known as?

• Oil drop experiments

• Radioactivity studies

• Discharge tube experiments

• Alpha particle scattering experiments

In discharge tube experiments conducted at very low pressures and high voltage, electricity flows in the form of rays originating from the cathode. What are these rays called?

• Anode rays

• Gamma rays

• Cathode rays

• X-rays

What observation in discharge tube experiments demonstrated that cathode rays travel in straight lines?

• The shadow of an object placed in the path of the rays

• The deflection of rays by electric fields

• The production of X-rays

• The emission of light from the cathode

Which property of cathode rays suggested they consist of negatively charged particles?

• They travel in straight lines.

• They produce mechanical effects, like rotating a paddle wheel.

• Their behaviour in electric and magnetic fields is similar to that expected from negatively charged particles.

• They possess a heating effect.

According to the experiments described, what characteristic of cathode rays remains constant regardless of the gas used in the tube or the nature of the electrodes?

• The color of the glow produced

• The speed of the rays

• The charge-to-mass (e/m) ratio

• The heating effect produced

In 1897, J.J. Thomson determined the charge-to-mass ratio (e/m) of electrons by measuring their deflection under the simultaneous influence of which fields applied perpendicularly to each other?

• Gravitational and electric fields

• Electric and magnetic fields

• Gravitational and magnetic fields

• Only an electric field

R.A. Millikan measured the charge on the electron in 1909. What was the name of the method he used?

Using the experimentally determined values for the charge (e) and the charge-to-mass ratio (e/m) of an electron, how is the mass (m) of the electron calculated?

• m = e * (e/m)

• m = (e/m) / e

• m = e / (e/m)

• m = e + (e/m)