MEASUREMENT – SC.10                                         Feb.22

1.  We use more precise units like mm to measure small things and larger units like  m and km to measure larger things.

Example: coin in mm, height in cm, distance in km

2.  A tool like a digital balance is precise to 0.01 g.

3. A triple beam balance also measures to the 0.01 g

Examples:  45.54 g,  45.50 g

4.  A spring balance measures in grams(g) and newtons (N)

Gravity pulls with a force measured in newtons!

(100 g = 1 N)

5.  Know how to read a graduated cylinder

- Count divisions properly

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            90             110       Answer= 99.

6.  Know how to measure volume by displacement.

Height of water   200.0 mL

Water and ball     240.0 mL

Volume of ball        40.0 mL

7.  Know how to calculate volume using a formula

Rectangular Prism = length x width x height = cm³

8.  Density is = mass/volume

Example golf ball  =  43.50  g / 40.0 mL = 1.14  g/mL

Notice:  If an objects density is greater than 1 it sinks!

              If it is less  than 1 , it floats.

             This is because the density of water = 1.0 g/mL

9.  Estimate the volume using mL or cm³  !  not grams.