1. Chapter 13
Fluid Pressure

2. Chapter 13
Water pressure increases as depth increases. The pressure is constant, and it is exerted equally in all directions.
The atmosphere is also a fluid. Air pressure decreases as the altitude increases.

3. Chapter 13
Pascal’s Principle- a change in pressure at any point in a fluid is transmitted equally and unchanged in all directions throughout the fluid.
*Hydraulic system- device that uses pressurized fluid acting on pistons of different sizes to change a force.
In a hydraulic lift system, an increased output force is produced because a constant fluid pressure is exerted on the larger area of the output piston.

5. Chapter 13
Bernoulli’s Principle- as the speed of a fluid increases, the pressure within the fluid decreases. (named for Swiss scientist Daniel Bernoulli)
Bernoulli’s Principle is the explanation for why birds and planes can fly. There is a pressure difference between the top and the bottom of the wing that creates an upward force called lift.*
Also explains spray bottles.

7. Chapter 13
*Buoyancy- ability of a fluid to exert an upward force on an object placed in it.
Buoyancy results in the apparent loss of weight of an object in a fluid.
*Buoyant force- upward force that acts in the opposite direction of gravity.

8. Chapter 13
Archimedes’ Principle- the buoyant force on an object is equal to the weight of the fluid displaced by the object.
If an object is less dense than the fluid it is in, it will float. If the object is more dense than the fluid it is in, it will sink.
When the buoyant force is equal to the weight, an object floats or is suspended. When the buoyant force is less than the weight, the object sinks.