Internal 3 Credits DO NOW: Read The ping-pong balls on page 167.

 How would you calculate the volume of all four balls?  Length of cardboard tube, in terms of r?  Expression for the volume of space inside the tube (hint: think about r)?  Volume of empty space inside tube when balls are in it?  Write down the ration of all four balls to volume of air inside the tube outside balls?  If we have 3 balls, how does the ration change?

 Go to page 167 and do the following exercises individually:  1, 3, 6 and 13

 Get into teams to do the next set of exercises.  One person needs to record the answers and another need to present if called on.  Complete exercise on page 169.

 How many forms can H 2 O take?  Solid  volume in cm 3 or m 3  Liquid  volume usually measured in mL, L or kL.  Use term capacity to describe the volume of liquid in a container.

 When we talk about volumes of liquids we often use the word capacity, rather than volume. 1 cm 3 holds 1 mL  1000 cm 3 holds 1000 mL  1000 cm 3 holds 1 L Also 1 m 3 holds 1 kL (= 1000L) The basic unit of capacity is the litre (L). 1 litre (L) = 1000 millilitres (mL) 1 kilolitre (kL) = 1000 litres (L) 1 ml of water weighs 1 gm Note: Usually use small letters for metric units like mm or cm but exception is L for litres so that we do not confuse it with the number 1.

 Lawnmower fuel tank shown right.  Calculate capacity in mL.  How many times can it be filled using 5 L can of petrol?  Volume = 15x10x5 = 750 cm 3  1 cm 3 = 1 mL  Volume = 750 ml  Number of times = 5000 mL / 750 mL = 6.6 times  Round to 6 times.

 Do the following exercises (14.01 pg 173):  1, 3, 5, 6, 8, 12, 15, 17