2. Measurement Definitions, Units, and Equipment

Test 1 Review

Test 1 topics 1. Scientific Method 2. Measurement definitions, units, and equipment 3. Control, Independent, and dependent variables 4. Metric conversions 5. Significant Figures with measuring 6. Significant Figures with calculations 7. Accuracy and Precision 8. Data table format

1. Comment on the accuracy and precision of these basketball free-throw shooters: a. 99 of 100 shots are made b. 99 of 100 shots hit the front of the rim and bounce off c. 33 of 100 shots are made; the rest miss

2. How many significant figures are in each of these measurements? a. 143 g d. 1.072 km b. 0.074 cm e. 10800 cal c. 8.750 x 10-2 ng f. 5.00 dm3

3. Round off each of these measurements to three significant figures a. 98.473 L d. 12.17 C b. .00076321 cg e. .00748983 x 104 mm c. 57.048 m f. 1764.9 mL

4. Round off each of the answers correctly a. 8.7 g + 15.43 g + 19 g b. 4.32 cm x 1.7 cm c. 853.2 L – 627.443 L d. 38.742 kg / 0.421 e. 5.40 m x 3.21 m x 1.871 m f. 5.47 m3 + 11 m3 + 87.300 m3

5. Water with a mass of 35.4 g is added to an empty flask with a mass of 87.432 g. The mass of the flask with the water is 146.72 g. after a rubber stopper is added. Express the mass of the stopper to the correct number of significant figures.

6. Match the approximate volume with each item. a. an orange (1) 30 m3 b. a basketball (2) 200 cm3 c. a van (3) 20 L d. an aspirin tablet (4) 200 mm3

7. Astronauts in space are said to be weightless. Explain why it is incorrect to say that they are massless. 8. A weather balloon is inflated to a volume of 2.2 x 103 L with 37.4 g of helium. What is the density of helium in grams per liter?

9. Which is larger? a. centigram or milligram b. liter or centiliter c. calorie or kilocalorie d. millisecond or centisecond e. mm3 or cm3

10. A cheetah has been clocked at 112 km/hr over a 100 m distance. What is this speed in m/s?

11. Make the following conversions. Express answers with correct significant figures. a. 74. cm to meters b. 8.32 x 10-3 kg to grams c. 555 L to cubic centimeters d. .00527 cal to kilocalories e. 8.6 g to milligrams f. 9.62 kilojoules to joules g. 9.52 m to millimeters h. 37. cm/sec to km/hr i. 127.6 mm/sec to cm/min j. 16.mm3 to mL

12. In the lab you add an equal amount of sugar to three beakers of hot water. You cool the three beakers to three different temperatures and examine the amount of sugar that precipitates. What are the independent and dependent variables? Test 1 Review answers

1. a. very accurate and precise b. not accurate, but very precise c. poor accuracy, but relatively precise 2. a. infinite b. 2 c. 4 d. 4 e. infinite f. 3 3. a. 98.5 b. .000763 c. 57.0 d. 12.2 e. 74.9 f. 1.76 x 103 4. a. 43.1 g b. 7.3 cm2 c. 225.8 L d. 92.0 kg e. 32.4 m3 f. 103.77 m3 5. 23.9 g 6. a. 200 cm3 b. 20 L c. 30m3 d. 200 mm3 7. weight is dependent on gravity and changes when gravity changes, mass is dependent of # of particles 8. .017 g/L 9. a. cg b. L c. kC d. cs e. cm3 10. 31.1 m/s 11. a. .74 m b. 8.32 g 12. temp is independent; amt of sugar is c. 555000 cm3 dependent d. .00000527 kilocal e. 8.6 x 103 mg f. 9.62 x 103 joules g. 9.52 x 103 mm h. 1.3 km/hr i. 765.6 cm/min j. 0.016