Question

Observe Fig. of the gold foil experiment. Predict the observations you would expect if the gold foil in the experiment were made thicker. Also, draw a simple diagram to show the observations you expect.

Hint: Compare thin foil vs thick foil. How does the thickness affect the chances of hitting a nucleus?

Answer 1

If the gold foil were thicker, more gold atoms would lie in the path of the α-particles, so more particles would be deflected or scattered. Most α-particles would still pass straight through, but fewer would pass undeflected than with thin foil. More particles would be deflected at small and large angles, and a larger number would bounce back. Diagram: draw a horizontal beam of α-particles hitting a thick gold foil drawn as a block of many atoms. Show most arrows passing straight through, several arrows bent at different angles, and a few arrows reflected back towards the source.