Chapter 9 - Liquids Flashcards
What are the 3 states of matter?
solid, liquid, gas
Properties of solids
- hold their shapes
- rigid
- not easily deformed
Properties of liquids
- do not hold their shapes
- easily deformed by outside forces
- flow and take the shape of their containers
- incompressible (fixed volume)
Properties of gases
- do not hold their shapes
- easily deformed by outside forces
- expand to fill their containers
- can be compressed
define pressure
Force divided by the area over which force is exerted.
Pressure = Force/Area
What does liquid pressure depend on? What happens as you go deeper?
The pressure a liquid exerts on the sides and walls of its container depends on its depth and density. As depth increases, gravity causes the pressure to increase. So, the pressure is greater at the bottom of the liquid than it is at the top.
In what direction does a liquid exert force on an object?
The force exerted by a fluid on a surface is always perpendicular to the surface. The force of a liquid pushing against the walls of its container is perpendicular to the surface of the walls.
Pascal’s Principle
A change in pressure at one part of the fluid will be transmitted undiminished to all other parts of the fluid.
What is buoyant force?
The upward force acting on an object in liquid due to the liquid pressure. Because the pressure is greater at the bottom of the liquid, it pushes up on the submerged object.
Archimedes Principle
Buoyant force is equal to the weight of the fluid displaced by an object.
How do you know if something will sink or float?
If something is more dense than a liquid it will sink. If it is less dense than a liquid it will float.
What is viscosity?
How tightly the molecules in a liquid stick together.
What happens to viscosity when temperature changes?
When temp increases, viscosity decreases because the molecules are less tightly bound together. When temp decreases, viscosity increases and the liquid gets thicker because the molecules hold together more tightly.
What is surface tension?
The tension of the surface of a liquid due to the cohesive forces between its molecules.
