DENSITY

Meaning

  Density is the mass of an object divided by its volume. Density often has units of grams per cubic centimeter (g/cm³). Remember, grams is a mass and cubic centimeters is a volume (the same volume as 1 milliliter).Also the if an object's density lower than the surroundings,the object will float.

  Take a look at the two boxes below. Each box has the same volume. If each ball has the same mass, which box would weigh more?

The box that has more balls has more mass per unit of volume. This property of matter is called density. The density of a material helps to distinguish it from other materials. Since mass is usually expressed in grams and volume in cubic centimeters, density is expressed in grams/cubic centimeter.

CALCULATION/FORMULA:

We can calculate density using the formula:

OR

Density= Mass/Volume

EXAMPLE:

You have a rock with a volume of 15cm3  and a mass of 45g.What is its density?

Solution:

density=mass/volume

            =45g/15cm3

                =3 g/cm³

^{A cork masses 1g with a volume of 40cm.What is its density?}

^Solution:

^{density=mass/volume}

           ^=1g/40cm3

           ^=0.25 g/cm3

Which one will float and will sink if the water density is 1.9 g/cm3?

If you want to find the amount of mass or volume this is the formula

TO CALCULATE AMOUNT OF DENSITY IN FASTER WAY,CLICK :

http://www.calculator.net/density-calculator.html

As a revision or practice:

http://www.algebralab.org/practice/practice.aspx?file=word_density.xml

http://www.kchemistry.com/PDF's/Density%20exercises.pdf

http://www.middleschoolchemistry.com/lessonplans/chapter3/lesson1

Density of Air

1.225 kg/m³

The basic principle behind hot air balloon physics is the use of hot air to create buoyancy, which generates lift. A hot air balloon consists of a large bag, called an envelope, with a gondola or wicker basket suspended underneath. A burner (with power typically of several megawatts) sits in the basket and is used to heat the air inside the envelope through an opening. This heated air generates lift by way of a buoyant force.

   

Hot air balloon rises because the hot air inside it have less dense than air outside of the hot air balloon.

Density of Water

between 1.8 and 1.95

If the boat weighs less than the maximum volume of water it could ever push aside (displace), it floats. But it sinks into the water until its weight and the upthrust exactly balance. The more load you add to a boat, the more it weighs, and the further it will have to sink for the upthrust to balance its weight.

CONCLUSION:

THE HIGHER DENSITY IS ON BOTTOM

THE LOWER DENSITY IS ON  TOP