2Measurement What is measurement? any standard of comparison, estimation, or judgment
3Why do we measure things? To give informationTo 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 geckoHeight of a Basketball player, compared to horse jockeyWeight of an elephant, compared to mouse
4What kinds of measurements can you take? LengthVolumeMassTemperature
5U.S.A What kind of scale does the U.S. use? U.S. Customary scale Including inches, feet, miles
6The World & The Scientific Community Uses the SI Systeme Internationale d’Unites (French), or Metric SystemAs 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 10Today all countries except the United States, Burma, and Liberia use the metric system
7Why 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!
8Length Basic unit of measure = meter What would you measure in meters? 1. How far you throw a softball2. A person’s height3. Measure height of a room’s wall
9Units for metric length Unit Abbreviation Meaning1.Kilometer Km m2.Hectometer Hm 100m3.Dekameter Dkm 10m4.Meter m 1m5.Decimeter dm .1m6.Centimeter cm .01m7.Millimeter mm m
10Multiples of Ten 10 Hm = 1 Km 10 Dkm = 1 Hm 10 m = 1 Dkm 10 dm = 1 m 10 cm = 1 dm10 mm = 1 cm
19Measuring 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 notch3. 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.
20Mass vs. WeightMass – the amount of matter an object contains (the amount of stuff)IT DOES NOT CHANGEWeight- force of gravity on an objectCan 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.
21Units for measuring mass: Unit Abbreviation Meaning1. Kilogram Kg g2. Hectogram Hg 100g3. Dekagram Dkg 10g4. Gram g 1g5. Decigram dg .1g6. Centigram cg .01g7. Milligram mg g
22Temperature Unit of measure : Celsius (C ) Example: Water freezes at 0° Cand boils at 100° C
23TimeTime is simply distinguishing which of two events is earlier and which laterTime is measured in different incrementsYearsMonthsDaysHoursMinutesSeconds