CK-12 Physical Science - For Middle School

http://www.ck12.org Chapter 5. Atoms

FIGURE 5.12

Rutherford shot a beam of positive alpha particles at thin gold foil.

He compared them to planets orbiting a star. That’s why Rutherford’s model is called the planetary model. You can
see it inFigure5.13.

FIGURE 5.13

This model shows Rutherford’s idea of

the atom. How does it compare with

Thomson’s plum pudding model?