Students to complete their own notes.

- Studied the Cathode Ray Tube

- Found the mass to charge ratio of an electron

- Led to the Plum Pudding Model

English Physicist

Discovered the Electron

The Design of the Cathode Ray Tube

So! Thompson has discovered the electron, and it must live inside atoms.

It is much less massive than the the atom itself, so perhaps we have little electrons stuffed into the ‘rest’ of the atom like raisins in the oatmeal, or:

Plum Pudding...

◦Measured minimum electric charge that could be carried by a particle (1905)

◦This was the charge of the electron

◦Enabled him to find the mass of the electron

American Physicist

Performed the Oil Drop Experiment

Millikan’s Oil Drop Experiment

Used To Determine the Charge of an Electron

New Zealand born physicist

Worked with nuclear radiation

Performed the Gold Foil Experiment

Discovered the nucleus (1910)

Discovered the proton (1918)

The Gold Foil Experiment

Demonstrated that the atom contains a nucleus which is:

a. Very tiny – most of the particles missedb. Positively charged – some were deflectedc. Very dense – some bounced off

Discovered the neutron in 1932

In college he stood in the wrong line.

He wanted to be a mathematician, but was in the line for physics and was too embarrassed to switch.

Instead he became a famous physicist.

End!

The story’s not over, but we’ll pick it up in chapter 4.