Measurement Metric system

Why do we use the metric system?

Metric system  A decimal system of units based on the meter as a unit length, the gram as a unit mass, and the liter as a unit volume.  Base ten system  Other base ten systems?

Time?

 Base units: gram (mass) meters (length) liters (volume)  Prefixes: kilo hecta deka deci centi milli How to convert between the unitsHow to convert between the units:

Measurement  Precision and accuracy

 Accurate - In physical science it means 'correct'. A measurement is accurate if it correctly reflects the size of the thing being measured.  Precise means "exact, In physical science it means "repeatable, reliable, getting the same measurement each time."

 Mass

Mass  Mass- amount of matter in an object. How is it different than weight? 1) Mass is a measurement of the amount of matter something contains, while weight is the measurement of the pull of gravity on an object (measured in Newtons). 2) The Mass of an object doesn't change when an object's location changes. Weight, on the other hand does change with location.

 What tool do you use to measure mass? triple beam balance  How to use a triple beam balance: online.com/objects/viewobject.aspx?I D=gch202

Gum Lab 1.Put wrapped gum in a cup and find the mass. 2.Chew Gum for 10 minutes (we will be taking notes during this time). 3.After 10 minutes, put the gum back in the cup and find the mass.

Volume

 Volume – the amount of space something takes up. What tool do you use to find volume of a liquid? Graduated Cylinder. How to use a graduated cylinder: online.com/objects/viewobject.aspx?id= gch302

 Beaker activity

 How do you find the volume of a solid? LxWxH tool: ruler

Length

 Length- amount of distance between two points.  Ruler

Density

 Density –  the amount of mass in a given volume d=m/v

 What has more mass, a kilogram of lead or a kilogram of feathers?