1. MICROSCOPIC MEASUREMENT
Millimetres
Micrometres
Nanometres
Angstroms

2. MILLIMETRE
Symbol: mm
Activity: Take a ruler and draw a line that is only 1mm in length. Use this extremely short line to help you visualize the next smaller unit of microscopic measurement, the micrometre.

3. MICROMETRE 1 micrometre= 1/1000 of a mm. Symbol:um
Another way to describe this measurement would be to say that there are 1000 micrometres in a single mm.
Activity: Divide your 1 mm line in half. How many micrometres are there on either side of the line?
ANSWER: 500
Can you divide the mm into 1000 pieces?

4. NANOMETRE Symbol: nm 1nm= 1/1000 of a micrometre
Another way to express this measurement would be to say there are 1 million nanometres(nm) in a single mm.
Try to visualize: Were you able to visualize your 1mm line cut into 1000 pieces? Now take one of those pieces and cut it into another 1000 pieces to represent a nm.

5. ANGSTROM Symbol: Å 1 Å = 1/10,000 of a micrometre
There are 10 million Angstroms in a single mm.
Angstroms and nanometres are units that can be measured by an electron microscope.