For Part 1, each group needs:

• plastic bottle with 1.5 mm hole drilled into cap
• 2 plastic cable ties
• ring stand with clamp holder and ~10 cm rod
• scissors
• Simple Coulter Counter Lab Handout, one per person

For Part 2, each group needs:

• 1 kΩ resistor
• 9V battery
• insulated wire
• 9V battery snap connector

For Part 3, each group needs:

• computer with data-acquisition and Microsoft Excel® software applications
• data-acquisition equipment (see note below; also see Troubleshooting Tips section)
• voltage probes

For Part 4, each group needs:

• 600 ml beaker
• stirrer

For Part 5, each group needs:

• a second 600 ml beaker

For Part 6, each group needs:

• Vial of "paint sample" with 1 mm diameter particles to be counted. (Make sample as described in Procedure section, by putting ~0.5 ml of grinding media plastic particles in a vial and filling with salt water solution [the same solution used elsewhere in the lab].) One source for plastic particles is Grinding Media Depot® at http://www.norstoneinc.com/our-products/beads/grinding-media-depot/; the grinding media come in a range of sizes; we suggest ~1mm-sized particles of PMMA, which has the density closest to water. Note: When we ordered the grinding media, a minimum order of $50 was required, which was far more than you would use for multiple years worth of classes.

For Part 1, to share with the entire class:

• hole punch

For Part 2, to share with the entire class:

• electrical tape
• wire strippers

For Part 4, to share with the entire class:

• liquid soap (enough for 2-3 drops per group)
• NaCl salt (enough for 0.3 g per group)
• scale (to measure salt in grams)
• water

For Part 5, to share with the entire class:

• printer

For teacher:

• drill and bit (to create 1.5 mm holes in plastic bottle caps)

A note on data acquisition equipment: The sample data provided for this lab was obtained using the following two different pieces of equipment.

• The Vernier LabQuest® Mini ($149) comes with the LoggerPro Lite® software and has a maximum sampling rate around 1000 samples/second when taking data for 30 seconds. A separate voltage probe ($12) must also be purchased for this lab.
• The DATAQ® DI-148U ($50) has a sampling rate of 240 samples/second when using the software provided and does not require a separate probe.