fluid mechanics, gravity

fluid

- nonsolid state of matter in which the atoms or molecules are free to move past each other

- gas/liquid

Density

The concentration of matter in an object

Specific Gravity

- density relative to water

- ratio of density of an object to the density of the reference material

Pressure

is the magnitude of the force on a surface per unit area

1.01 x 10^5

pressure at sea level

Pascal's Principle

"Pressure applied to a fluid in a closed container is

transmitted equally to every point of the fluid and to the walls of the container."

Archimedes' principle

"Any object completely or partially submerged in a fluid experiences an upward buoyant force equal in the magnitude to the weight of the fluid displaced by the object"

Bernoulli's principle

"In a flowing fluid, an increase in the fluid's velocity is

accompanied by a decrease in pressure, and

conversely, a decrease in velocity is accompanied

by an increase in pressure, provided there is no

change in the fluid's density or energy losses due to

friction.

Newton's Law of Universal Gravitation

"Any two objects attract each other with a gravitational force proportional to the product of their masses and inversely proportional to the square of the distance between them."

Gravitational Field

force surrounding a body of finite mass in which another body would experience an attractive force that is proportional to the product of the masses and inversely proportional to the square of the distance between them.

Gravitational Field Strength

gravitational force per unit mass on an object.

Escape Velocity

the velocity needed by an object in order to escape the effect of the gravitational force on it.

Geocentric Model

- Claudius Ptolemy

- this theory assumed the Earth is fixed at the center of the

universe where the planets and other celestial bodies move around it in circles called orbits.

Heliocentric Model

- Nicholas Copernicus

- this theory places the Sun at the center of the Solar System where the Earth and other planets move around it in circular orbits.

Tycho Brahe and assistant Johannes Kepler

- observed the motion of the planets

1. Law of Orbits

"The planets move in elliptical orbits with the sun at one of

the foci of the ellipse."

2. Law of Areas

"A straight line drawn from the Sun to the planet sweeps equal areas at equal intervals of time."

3. Law of Periods

"The square of the periods of the planets are proportional to the cubes of their average distance from the sun."