Physics density

• In solids, the atoms are as close together as they can possibly get. They vibrate at a fixed position. (They do not move)
• In liquids, the atoms are close together but with some space between. While vibrating atoms in a liquid move around from one place to another
• In gases, the atoms have large spaces between them. The atoms in a gas move around very fast while continuosly bumping into each other
• Evaporation is when a liquid becomes a gas
• Condensation is the process of water vapuor turning back into a liquid.
• mass is the amount of matter (atoms) that make up a object
• mass is measured in kilograms
• mass is measured using a balance
• Why is mass and weight different?

  Mass is the mass of an object and weight is the force exerted on the object due to gravity
• The volume of a liquid can be found using a measuring cylinder
• While taking the reading it is important that the eye is level with the bottom of the curved surface of the liquid it is called meniscus
• We use a measuring cylinder for irregular objects such as an egg a stone
• Density is how much mass is contained in a given volume
• Density is measured in kg/m3 or g/m3
• to find the mass we use equation m=Vp
• to find the volume we use the equation V=m/p
• To find the mass you use a balance
• To find the volume you use a measuring cylinder
• If two objects are made from the same material, it's density will be the same. But their mass and volume will be different
• How can i change the density?

  By heating up the object until it melts
• If the object is less dense than the liquid or gas, it will float.
• If the object is denser the object will sink.
• The density of water is 1g/cm3
• So if the density of wood is o.80g/cm3. It will float or sink?

  Float
• Density of a material is the mass per unit volume