Lab Exercise 1

Physics Lab 1 Tuesday, June 1, 2010 Name __________________
Dr Dave Menke, Instructor, Upward Bound at Pima Community College

I Title: Density of Water

II Purpose: Practice in Measurement, and to find Density of Water

III Equipment: beaker (50-ml) or Pyrex measuring cup, graduated cylinder (50-ml), digital scale, water

IV Procedure:
1. Weigh (in grams) dry beaker/cup. Record.
2. Use graduated cylinder to add 25 50 ml of water to beaker or ¼ cup water
3. Weigh (in grams) the beaker/cup with the water in it. Record.
4. Find the weight (grams) of the water (subtract #1 from #3). Record.
5. Find the density (grams / ml) of the water (divide #4 by 25 ml). Record.
(If using a Pyrex measuring cup, conversions from cups to liters will be required)

V Data
1. Mass of dry beaker/cup ___________grams

2. Mass of beaker/cup + water ___________ grams

3. Mass of the water ___________grams

4. Density of water ___________ grams / ml

(The True Density of Water is 1.0 grams / ml or 1000 kg/m3)

VI Results: In this section, explain how successful you were at achieving the Purpose. [If you found (or were close) the density of water, then you were successful. If not, you were not.]

VII Error
A. Qualitative – sources of error
1. Personal – what things did you or your partner(s) do to screw things up, if anything at all?
2. Systematic – what was wrong with the equipment that caused the lab to go “bad”, or, what external factors (hurricane, earthquake, etc) contributed to difficulties in this lab?
3. Random – there are always random errors, unless you do this lab exercise 5 times and take an average
B. Quantitative – Find the Percent Error

[True Answer – Your Answer] / [True Answer] x 100% = ________%

VIII Questions
1. Which water is denser, salt water (ocean) or fresh water (lake or river)? Find the density of each.
2. What is denser, solid water (ice) or liquid water? Give an example.