Ch02b using si units

1,681 views

Published on

Published in: Education
  • Be the first to comment

Ch02b using si units

  1. 1. Unit 1<br />Using SI Units<br />
  2. 2. Measurement Standard<br />An exact quantity that people agree to use for comparison.<br />* helps you get the same answer as other people<br />
  3. 3. What was used as the earliest measurement standards?<br />Body Parts<br /> * The question then, is WHO’S body parts?<br />The KING’S or QUEEN’S<br />
  4. 4. Is your hand or a body part a good standard of measurement?<br />* no<br />* people’s hands are not the same size <br />* get different answers<br />
  5. 5. In order for any measurement to MAKE SENSE; two things must be included.<br />1.) a number<br />2.) a unit<br />
  6. 6. Every type of measurement has a base or central unit.<br />* meter (distance or length)<br />* liter (volume)<br />* gram (mass)<br />* second (time)<br />
  7. 7. Adding a prefix to a base (central) unit, you can create a whole new unit to measure any object.<br />
  8. 8. Prefixes Used When Measuring:<br />Large Objects<br />kilo = 103<br />hecto = 102<br />deka = 101<br />Small Objects<br />deci = 10-1<br />centi = 10-2<br />milli = 10-3<br />
  9. 9. Measurements that can be made<br />Length<br />Mass<br />Temperature<br />Time<br />Area<br />Volume<br />Density<br />Weight<br />
  10. 10. Length<br />The distance between two points.<br />Base (central) units of length<br />* (US) FOOT [ft]<br />* (SI) METER [m]<br />
  11. 11. Length<br />Length of an object or the distance between two points is measured using a METERSTICK.<br />
  12. 12. Mass<br />“A body of coherent matter.”<br /> * a collection of stuff joined to form an object<br />Base (central) units of mass<br />* (US) SLUG [slug]<br />* (SI) KILOGRAM [kg]<br /> sometimes gram [g]<br />
  13. 13. Mass<br />Mass is measured using a BALANCE.<br />
  14. 14. Temperature<br />Measurement of how hot or cold something is.<br />
  15. 15. Temperature<br />Base (central) units of temperature<br />* (US) FAHRENHEIT [oF]<br />* (SI) CELCIUS [oC]<br /> > (SI) KELVIN [K]<br /> * this is an absolute scale<br />
  16. 16. Temperature<br />Temperature is measured using a THERMOMETER.<br />
  17. 17. Absolute Zero<br />The coldest possible temperature.<br />* temperature where ALL motion stops<br />* 0 Kelvin<br />* found by the formula: <br />K = oC + 273.16<br />
  18. 18. Time<br />Interval between two events.<br />Base (central) units of time<br />* (US) SECOND [s]<br />* (SI) SECOND [s]<br />
  19. 19. Time<br />Time can be measured using a CLOCK or a CALENDAR.<br />
  20. 20. Derived Units<br />Obtained by combining multiple units of measurement.<br />
  21. 21. Area<br />The amount of surface included in a set of boundaries.<br />Found by the formula:<br />* Area = lengthx width<br />
  22. 22. Area<br />What is the difference between length and width?<br />DIRECTION<br />
  23. 23. Area<br />Base units of area<br />* (US) FEET SQUARED [ft2]<br />* (SI) METERS SQUARED[m2]<br />
  24. 24. Volume<br />The amount of space an object occupies.<br />Easy with liquids & gases, harder with solids<br />* for a solid you may need the formula:<br />volume = l x w x h<br />
  25. 25. Volume<br />For a liquid or a gas all you need is a devise that is designed to measure volume.<br />* a beaker, a flask or a graduated cylinder<br />
  26. 26. Volume<br />Base (central) units of volume<br />* (US) GALLON [gal]<br />* (SI) LITER [L]<br /> sometimes centimeters cubed [cm3]<br />
  27. 27. Volume<br />1 milliliter equals<br /> 1 centimeter cubed.<br />* 1 mL = 1 cm3<br />
  28. 28. Density<br />The measurement of how thick, compact and solid an object is.<br />Relationship between the mass & volume of an object<br />
  29. 29. Density<br />Found by the formula:<br />* Density = mass ÷ volume<br />Expressed in g/Lorg/cm3<br />* a mass unit / a volume unit<br />
  30. 30. Weight<br />Measurement of the force of gravity pulling on the mass of an object.<br />Changes as gravity changes.<br />Base units of weight<br />* (US) POUND [lb]<br />* (SI) NEWTON [N]<br />
  31. 31. Weight<br />Weight is measured using a SPRING SCALE.<br />
  32. 32. MASS and WEIGHT are NOT the same thing!<br />
  33. 33. Physical Properties<br />Characteristics of a substance that can be used to identify it.<br />Color<br />Shape<br />Texture<br />State of matter<br />Size<br />All measurements<br />(changing a physical property does NOT change the substance)<br />
  34. 34. The End<br />

×