Volume: the amount of space something takes up! BATHTUB

What happens to the level of the water when you step in a bathtub?

What happens to the level of the water when you step in a bathtub?

Volume or Water Displacement Water is generally incompressible. An object will displace a volume of water equal to the volume of the object itself when submerged. Both cm3 and ml measure volume or the amount of space an object takes up. 1ml is = 1cm3 Water displacement is useful for determining the volume of irregularly shaped objects. DETENTION! Chips vs Water for incompressibility Make a mess squish some water TOILET WATER

If you place a large screw into a graduated cylinder with 60ml of water in it and the water level rises to 80ml, what is the volume of the screw? 1ml = 1cm3 ---60ml Hand out graduated cylinders

If you place a large screw into a graduated cylinder with 60ml of water in it and the water level rises to 80ml, what is the volume of the screw? ---80ml ---60ml ---60ml

If you place a large screw into a graduated cylinder with 60ml of water in it and the water level rises to 80ml, what is the volume of the screw? ---80ml ---60ml ---60ml The difference is 20ml

20cm3 1ml = 1cm3 ---80ml ---60ml ---60ml If you place a large screw into a graduated cylinder with 60ml of water in it and the water level rises to 80ml, what is the volume of the screw? 20cm3 1ml = 1cm3 ---80ml ---60ml ---60ml The difference is 20ml

If you place a large screw into a graduated cylinder with 57 If you place a large screw into a graduated cylinder with 57.4ml of water in it and the water level rises to 81.6ml, what is the volume of the screw? ---81.6ml ---57.4ml ---57.4ml

Final – initial position If you place a large screw into a graduated cylinder with 57.4ml of water in it and the water level rises to 81.6ml, what is the volume of the screw? Get the difference! Final – initial position 81.6ml – 57.4ml = 24.2ml ---81.6ml ---57.4ml ---57.4ml

Final – initial position If you place a large screw into a graduated cylinder with 57.4ml of water in it and the water level rises to 81.6ml, what is the volume of the screw? Get the difference! Final – initial position 81.6ml – 57.4ml = 24.2ml ---81.6ml ---57.4ml ---57.4ml 24.2cm3 1ml = 1cm3

YOUR TASK Read at the base of the meniscus! Measure the volume of a large screw ________ Measure the volume of a 10g mass________ What is the screw’s density?________ A paper clip is too small to accurately measure its volume. Come up with a method that can be used to determine the volume of one paper clip. Write it down in your notebook. What is the volume of a single paper clip______ Read at the base of the meniscus! Keep it flat, read at eye level!

What if an object is too big to fit in a graduated cylinder? You might consider using a beaker instead but in general a graduated cylinder is far more accurate at measuring volume than a beaker. So we can use something called an overflow can.

Overflow Can. Fill the can above the drain line with water. Let the excess drip out until the water is level with the drain. Now any object placed in it will cause the water to overflow through the drain.

Overflow Can. Fill the can above the drain line with water. Let the excess drip out until the water is level with the drain. Now any object placed in it will cause the water to overflow through the drain. Catch the water in a graduated cylinder or other device and measure its volume in ml. This is the volume of the object in cm3

CLASS ACTIVITY DENSITY Determine the density a rock: a 200g mass What metal is the mass made of? (use the internet to look up your density value). CLASS ACTIVITY Both metals the same, talk about error DENSITY

CLASS ACTIVITY Pattern? Determine the mass in grams of the following volumes of water: VOLUME (ml) MASS (g) 5 20 32 40 46 50 Pattern?

Water displacement is used to determine the volume of irregularly shaped objects. Milliliters (ml) and centimeters cubed (cm3) are interchangeable. 1ml = 1cm3 For H2O 1g = 1ml = 1cm3 Key Points