Definitions
What is density?
How compact something is. (The ratio of mass of an object to its volume)
What is an instrument for determining mass called?
A balance
Mass= 20 g.
Volume= 20 cc.
Density= 1 g./cm.^3
What do you use to measure the mass of an object?
A pan-balance
Copper Penny: Density of 8.9 g./cm.^3
Sink
What is mass?
The amount of matter in an object
What makes an object float?
If it is less dense than water so it overcomes the force of gravity.
Mass= 23 g.
Volume= 20 cc.
Density= 0.87 g/cm.^3
The following balls are the same size:
wooden ball: Mass of 7 g.
glass ball: Mass of 18 g.
black rubber ball: Mass of 10 g.
Why are their masses different?
Mass is the amount of matter in an object. If an object has more matter (like a desk), the mass will be higher. If the object has less matter (like a window fan), the mass will be lower.
Block of Wood: Density of 0.68 g./cm.^3
Float
What is volume?
The amount of space occupied by an object
What does it mean to give the serial order of something?
To arrange data in some type of order.
Mass= 22 g.
Volume= 20 cc.
Density= 1.1 g/cm.^3
You fill up a medicine cup with 20 cc. of water and then put in a clay ball. The medicine cup now measures 30 cc. What is the volume of the clay ball?
10 cc.
Vegetable Oil: Density of 0.93 g./cm.^3
Float
What does it mean to calibrate something?
To balance a scale or a double-pan balance.
The amount of liquid pushed aside in a container by an object is called...
displacement
Mass= 21 g.
Volume= 20 cc.
Density= 1.05 g./cm.^3
On a rainy or snowy day, which is more dense: the air or the clouds?
The clouds
Piece of Coal: Density of 1.2 g./cm.^3
Sink
What is weight?
The amount of gravitational pull on an object.
What is the equation to find density?
Mass divided by Volume =Density
Put all of the densities in order based on color from least dense to most dense.
Blue- 1 g./cm.^3
Red- 0.87 g./cm.^3
Green- 1.1 g./cm.^3
Yellow- 1.05 g./cm.^3
Red, Blue, Yellow, Green
You fill up a medicine cup with 20 cc. of water and then put in a clay ball. The medicine cup now measures 30 cc.
How does this help you to find the volume?
You are using the displacement of the water to see how much room the clay ball takes up.
Wooden Ball: Density of 0.99 g./cm.^3
Float, but it will bob up and down in the water.