Pressure

• when is gas felt as pressure

  when the gas particles move randomly in every direction and they exert forces on their container
• when does an object float

  if it weighs less than the weight of the water it displaces
• what does pressure in a liquid vary with

  depth and density
• what is the buoyancy force

  the upwards force that counteracts the weight of the floating object - equal to the weight of the fluid displaced by the object