EXPERIMENT

In this activity, you will pour sand through two narrow slits, 1.0 cm apart, cut into the bottom of a paper cup. The bottom of the paper cup needs to be approximately 0.5 cm from the paper covered tabletop.

PREDICTION

(i) Sketch your prediction of how the sand will pile up after it has passed through the slits. Draw the profile of the sand as it would look when viewed from the side. Show the slits in your diagram.

(ii) Provide reasoning for your prediction in one or two sentences.

PROCEDURE

(i) Cut two narrow slits in the bottom of a paper cup 1.0 cm apart.

(ii) Hold the paper cup with the slits in the bottom just above a white piece of paper. Carefully pour sand into the cup and tap it gently to allow some of the sand to pass through the slits (see Figure 1).

OBSERVATIONS AND QUESTIONS

01. Sketch a profile of the pile of sand.

02. Does the profile of the sand match your prediction? Why does the sand form the observed shape?

03. Grains of sand are localized particles. How do two grains of sand interact when they arrive at the same location at the same time?

04. Make a general statement about how classical localized particles behave when passing through a double-slit apparatus and describe the pattern they make after they have passed through the apparatus.