2. Measurement-A Common Language Density, Time, & Temperature

3. Density

4. Density / Densidad The measure of how much mass is contained in a given volume. / Es la medida de cuanta masa esta contenida en un volumen específico.

5. The formula of density is: / La formula para densidad es: Density = Mass / Volume Densidad = Masa / Volumen

6. Comparing Densities - Inferring: Which item has the greater density? Comparando densidades – Infiriendo: Cual objeto tiene la mayor densidad? The bowling ball / La pelota de Bolear Since the bowling bowl has a greater mass, it has a greater density, even though both balls have the same volume. / Debido a que la pelota de bolear tiene la mayor masa esta tiene la mayor densidad. Auque ambas tienen el mismo volumen.

7. Density / Densidad Units of Density / Unidades de densidad

8. Why is density expressed as a combination of two different units? Porque la densidad es expresada como una combinación de dos unidades diferentes? Because density is actually made up of two other measurements – mass and volume – an objects density is expressed as a combination of two units / La densidad esta contituida por dos otras medidas la masa y el volumen, por lo tanto la densidad se expresa como una combinacion de las dos.

9. Two Common Units For Density / Dos unidades comunes para densidad. Grams per cubic centimeter (g/cm³) / Gramos por centimetro cúbico (g/cm³) Grams per milliliter (g/mL) / Gramos por mililitro (g/mL)

10. Math Practice: Práctica matemática: What is the density of a wood block with a volume of 125 cm³ and a mass of 57 g? Cual es la densidad de un bloque de madera con un volumen de 125 cm³y una masa de 57 g? Density = mass / volume / Densidad = masa / volumen Density = 57 g / 125 cm³ Densidad = 57 g / 125 cm³ Density = 0.46 g/ cm³ Densidad = 0.46 g/ cm³

11. Math Practice: What is the density of a liquid with a mass of 45 g and a volume of 48 mL? Prática matemática: Cuál es la densidad de un liquido con una masa de 45 g y un volumen de 48ml? Density = mass / volume Densidad = masa / volumen Density = 45 g / 48 mL Densidad = 45 g / 48 mL Density = 0.94 g/mL Densidad = 0.94 g/mL

12. Density / Densidad Densities of Common Substances / Densidades de sustancias comunes

13. The density of a substance is the ______for all samples of that substance. / La densidad de una sustancia es la _____ para todos las muestras de esa subtancia. Same / Misma

14. An object will float if it is _____ _____ than a surrounding liquid. / Un objeto flota si es _____ _____ que el liquido circundante. Less dense / menos denso

15. Figure 6: Applying Concepts: How could you use density to determine whether a bar of metal is pure gold? If the bar of gold has a density that is greater than or less than 19.3 g/cm³, then the sample is not pure gold. Densities of Some Common Substances SubstanceDensity (g/cm³) Air0.001 Ice0.9 Water1.0 Aluminum2.7 Gold19.3

16. Reading Checkpoint (page 53): Will an object with a density of 0.7 g/cm³ float or sink in water? An object that has a density of 0.7 g/cm³ will float in water (1 g/cm³) because it is less dense than water

17. Time

18. Units of Time

19. What is the SI unit used to measure time? The second(s) is the SI unit to measure time

20. Common Conversions for Time 1s= =60 s 1h=

21. Common Conversions for Time 1s=1,000 ms =60 s 1h=

22. Common Conversions for Time 1s=1,000 ms 1 min=60 s 1h=

23. Common Conversions for Time 1s=1,000 ms 1 min=60 s 1h=60 min

24. Time Measuring Time

25. Why would a stop watch be used to measure time in an important race? Because stop watches measure in units smaller than the second These measurements include the tenth and hundredth of a second

26. Reading Checkpoint (page 53) - How many milliseconds are in one second? 1,000 milliseconds

27. Temperature

28. Units of Temperature

29. A common unit to measure temperature is the ___ ___. Celsius scale

30. Water freezes at ______ and boils at ______. 0 °C 100 °C

31. The normal human body temperature is approximately ________. 37 °C

32. What is the official SI unit for temperature? The Kelvin Scale (°K) 0 °K = 273 °C

33. Figure 8: Measuring Temperature - Observing: At what temperature on the Kelvin scale does water boil? 373 °K

34. What is absolute zero? Absolute zero is considered by scientists to be the coldest temperature possible 0 °K or –273 °C

35. Temperature Measuring Temperature

36. What instrument is used to measure temperature? Thermometer