1 / 30

***METRICS***

***METRICS***. Measurement. What is measurement? any standard of comparison, estimation, or judgment. Why do we measure things? To give information

lilike
Télécharger la présentation

***METRICS***

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ***METRICS***

  2. Measurement • What is measurement? • any standard of comparison, estimation, or judgment

  3. Why do we measure things? • To give information • To compare things quantitatively (if a person had never seen or heard of these animals before, measurements would help that person compare them) • Length of a crocodile compared to a gecko • Height of a Basketball player, compared to horse jockey • Weight of an elephant, compared to mouse

  4. What kinds of measurements can you take? • Length • Volume • Mass • Temperature

  5. U.S.A • What kind of scale does the U.S. use? • U.S. Customary scale • Including inches, feet, miles

  6. The World & The Scientific Community • Uses the SI Systeme Internationale d’Unites (French), or Metric System • As early as the 17th century French scientist found it illogical to have so many measurement systems so they developed one universal system. • It is easy to use because it is in multiples of 10 • Today all countries except the United States, Burma, and Liberia use the metric system

  7. Why is it important to use only one scale of measurement in science? • Scientists need to be able to share and compare their work with other scientists easily. • It makes it less confusing!

  8. Length • Basic unit of measure = meter • What would you measure in meters? • 1. How far you throw a softball • 2. A person’s height • 3. Measure height of a room’s wall

  9. Units for metric length Unit Abbreviation Meaning 1.Kilometer Km 1000m 2.Hectometer Hm 100m 3.Dekameter Dkm 10m 4.Meter m 1m 5.Decimeter dm .1m 6.Centimeter cm .01m 7.Millimeter mm .001m

  10. Multiples of Ten 10 Hm = 1 Km 10 Dkm = 1 Hm 10 m = 1 Dkm 10 dm = 1 m 10 cm = 1 dm 10 mm = 1 cm

  11. King Henry Died Making Dead Cows Moo

  12. King Kilometer Henry Hectometer Died Dekameter Making Meter Dead Decimeter Cows Centimeter Moo Millimeter

  13. Let’s Practice! • Length • *Measure from the zero mark not the end of the ruler (meter stick) What is the measurement? Cm

  14. What is the measurement? • 263 mm • 26.3 cm • 2.63 dm • 0.263 m Cm

  15. One More, On Your Own What are these measurements in centimeters, and millimeters? A B C 8 9 10 Cm

  16. C= 10.5cm, 105mm B= 9.9Cm, 99mm A= 8.2cm, 82mm 8 9 10 Cm

  17. Mass, Temperature, and Time

  18. Mass Basic unit of mass: = gram (g)

  19. Measuring Mass Using a triple beam balance 1. Place object on the pan 2. Move rider on the middle beam notch by notch until the horizontal pointer drops below zero. Move the rider back one notch 3. Move the rider on the back beam notch by notch until the pointer again drops below zero. Move the rider back one notch. 4. Slowly slide the rider along the front beam until the pointer stops at the zero point. 5. The mass of the object is equal to the sum of the readings on the three beams.

  20. Mass vs. Weight • Mass – the amount of matter an object contains (the amount of stuff) IT DOES NOT CHANGE • Weight- force of gravity on an object • Can vary depending on location of object. • Example: • Your mass is the same on the moon and on the earth. • Your weight is different on the moon as compared to the earth. • You weigh less on the moon because the force of gravity is less on the moon.

  21. Units for measuring mass: Unit Abbreviation Meaning 1. Kilogram Kg 1000g 2. Hectogram Hg 100g 3. Dekagram Dkg 10g 4. Gram g 1g 5. Decigram dg .1g 6. Centigram cg .01g 7. Milligram mg .001g

  22. Temperature • Unit of measure : Celsius (C ) • Example: • Water freezes at 0° C and boils at 100° C

  23. Time • Time is simply distinguishing which of two events is earlier and which later • Time is measured in different increments • Years • Months • Days • Hours • Minutes • Seconds

  24. Volume and Density

  25. Volume - The amount of space an object takes up.

  26. Measuring Volume • Liquids • Unit of measure = Liters (L) or (ml) • Use a graduated cylinder • Measure from the bottom of the meniscus • Meniscus –the curved surface of a liquid 20 15 10

  27. Measuring Volume • Regular solids • Unit of measure = cubic centimeter (cm3) • Volume= length x width x height Or L x W x H= Volume • Example • Volume = 20cm x 6cm x 25cm = 3000 cm3

  28. Irregular Solids • Unit of measure= centimeters cubed (cm3). • BUT! Measured using ml • ml and cm3 are equivalent units! • Example: • Volume of a rock using a graduated cylinder

  29. Density • Density: How much mass in a given volume (How much “stuff” in a certain amount of “space”) • Formula: Density = mass D = M volume V

  30. Example: • A box has a mass of 400 g and a volume of 15 cm3. What is the density of the box? • Example: • Bowling ball vs. Beach ball • Same volume different mass • Which item is more dense?

More Related