C3-3: Physical Properties of Solid Materials

Apparatus

A large selection of different solid materials; \(1.5\text{V}\) cell; ammeter (\(0-1\text{A}\)); voltmeter (\(0-3\text{V}\)); 5 connecting leads; magnet; compass needle; triple beam balance; overflow can; \(1\text{L}\) and \(100\text{ml}\) measuring cylinders filled with water; small beaker; optical pin; \(0.5\text{m}\) ruler; Physics reference books; eye protection glasses.

PRECAUTIONS

1. Some materials shatter if stressed. Take care to protect your eyes!
2. Do not damage samples in the box marked DO NOT DAMAGE. Any other materials can be bent or damaged if you wish.

Procedure

1. Choose 8 different materials for testing. For each of the materials, perform the following tests. Tabulate the results in a large table. Use words and/or numbers in the table, do not just use \(\checkmark\) or \(\times\).
2. Name the material. Describe its molecular structure, giving the constituent elements.
3. Find its density. Is the material porous?
4. Find its resistance between two chosen points (in \(\Omega\)).
5. When illuminated with white light:
   1. What intensity and colors of light are reflected?
   2. What intensity and colors of light are transmitted?
   3. Is it opaque, translucent, or transparent?
   4. Is the reflection regular or diffuse?
6. Is the material a good or poor thermal conductor?
7. Are there ferromagnetic elements in the material?
8. Mechanical tests: (approximate only)
   1. Elasticity: is it a stiff material?
   2. Strength: is the material strong or weak?
   3. Hardness: is the material hard or soft?
   4. Is the material ductile or brittle?

NOTE: The bolded words in sections 3 to 8 have exact meanings in Physics. Make sure that you know these meanings (refer to text books for help).

Observations

Tabulate your observations for each of 8 selected materials.