UNITS OF MEASUREMNT Integrated Science Mrs. Morehouse

Why is measurement important?  Use it in daily life  Cooking  Construction  Decorating a room  Driving  Communication  You need to be able to communicate measurements and distances to other people

Why is measurement important?  Scientists try to find relationships between the quantities they measure use UNITS of measurement to do this  Measure the very largest and smallest things in the universe Smallest: mass of an electron = yg Largest: light years (distances between stars and galaxies)

There are many units of measurement! QuantityUnitSymbol Lengthmeterm Massgramg VolumeliterL TemperatureCelsiusC Timeseconds We use the INTERNATIONAL SYSTEM OF UNITS (SI) SI is used worldwide so scientists can easily compare measurements

There are also derived units of measurement! QuantityUnitSymbol Areasquare meterm2m2 Volumecubic meterm3m3 Densitygrams per cubic meterg/m 3 Speedmeters per secondm/s Derived units are made from a combination of units

Metric Prefixes  Make UNITS more convenient to use  Can make units LARGER or SMALLER Defined in multiples of 10  PREFIXES increase or decrease metric basic units(g, L, m) by a factor of 10

Prefixes

Metric Prefixes PrefixSymbolRelation to Basic Unit kilo-k1 km = 1000 m hecto-h1 hm = 100 m deka-da1 dam = 10m UNIT(m)1 m deci-d10 dm = 1 m centi-c100 cm = 1 m milli-m1000 mm = 1 m

Conversion Factors  A CONVERSION FACTOR is a ratio of equivalent measurements that is used to convert a quantity expressed in one unit to another For example: 1 km = 1000m so the conversion factor would be 1 km1000 m 1000 m I km OR They are opposites!

Steps to Making Conversions 1. Decide if you are converting to a LARGER or SMALLER unit. Convert 8 m to cm 3. Set up your conversion factor & cancel units. Multiply across top and divide by the bottom. 8 m 100 cm 1 m 800 cm 4. Does your answer make sense? (we were converting to a smaller unit, so we needed more of them. Did we get more?) 2. Write the original measurement

Let’s try these together: 2 m to km 5 cm to m 12 km to m 100 mm to m km 0.05 m 12,000 m 0.1 m

Metric Prefixes PrefixSymbolRelation to Basic Unit kilo-k1 km = 1000 m hecto-h1 hm = 100 m deka-da1 dam = 10m UNIT(m)1 m deci-d10 dm = 1 m centi-c100 cm = 1 m milli-m1000 mm = 1 m

Try these on your own: 6 m to km 3 m to mm 16 cm to m km 3000 mm 0.16 m

But wait! There is another way… Let’s jump!

Jump UP or DOWN the metric ladder to convert

1. Determine your starting point 2. Count the JUMPS to your end point 3. Move the decimal the same number of jumps in the same direction.