Upload
amandayoung313
View
2.045
Download
1
Embed Size (px)
DESCRIPTION
Citation preview
Behavior of Liquids and Gases: Archimedes’ principle
7SCIENCE Wed. April 13
Review: What are some factors that affect the behavior of liquids and gases?
• Diffusion- mixing of particles
• Pressure - Pascal’s principle– When pressure is applied to a point in
a liquid or gas the pressure will travel unchanged through the liquid or gas
Density and Archimedes’ principle• Every substance (solid, liquid or gas) has a density• Density refers to if particles in a substance are closely
packed together Density (g/mL)= mass (g)
volume (mL)
Higher density = particles are packed more closely
Lower density = particles are further apart
Density and Archimedes’ principleWhy do some objects float and others sink?
• If an object has a density lower than that of the surrounding liquid or gas, it will float
• OPPOSITE: If an object has a density higher than that of the liquid or gas, it will sink
Buoyancy and Archimedes’ principle• The idea of buoyancy is that objects tend
to float or sink in a liquid
• Buoyancy is a decrease in weight caused by an upward force in a liquid or gas
- Objects have a specific buoyancy
– Ex: floating in a swimming pool or lake
Archimedes’ principle states:An object will sink until the volume of liquid displaced equals the weight of the object (then it will float)
Application of Archimedes’ principle“Plimsoll line”- Line painted on the side of a ship or boat- If the boat is sitting low and the line is under the
water, the ship is overloaded (too heavy)