Zusammenfassung der Ressource
Chapter 3
- Pressure
- Formula: P=F/A
- As elevation increases, air pressure decreases.
- As depth increases, so does water pressure.
- If the area of an object is smaller and there is force applied on it, the pressure decreases, and vice versa.
- N/M^2 or Pa (Pascal) is the unit of measurement for pressure
- Pascal's Principle
- A force applied to a confined fluid transmits the increase in pressure equally to all parts of the fluid.
- Hydraulic Systems
- Bernoulli's Principle
- The faster a fluid moves, the lower the surrounding pressure.
- Blowing between balloons creates faster moving air which causes low pressure in between.
Higher pressure goes around.
- The faster a fluid moves, the lower its surrounding pressure becomes.
- Density
- Formula: D=M/V
- A rock sinks in water because the rock is denser than water.
- Buoyancy
- If the buoyant force on an object in water is less than the weight, the object will sink.
- Archimedes's Principle
- The buoyant force on an object is equal to the weight of the fluid that the object displaces.
- Beach ball in water; why can't you push it down?
- Heavy boats need a big buoyant force, so they have to
displace a lot of water. This helps them carry heavy cargo.
- Objects are lighter underwater because of buoyant force.
- If you change the volume of the object and the
density of the fluid, then the buoyant force
changes.
- If an object sinks, the density is greater than the liquid.
- A fluid is any matter that flows. Solids and plasmas do not flow.
- Fast cars have spoilers on their backs because they need to stick to the road. This is
provided by downforce, so a spoiler is used to slow down the air going over the car.