lunes, 20 de septiembre de 2010

the outer solar system

comet: a ball of rock and ice that orbits the sun

meteorid:a small asteroid wich may be far out in the solar system

meteor : a meteorid that enters Earth´s atmosphere and burns with a streak of light

meteoride:any part of a meteorid that reaches to Earth´s surface

the inner solar system

planet: a large body orbiting a star such as the sun

solar system : a star sushs as the sun and all the objects orbitng it

asteroid: a rocky metallic object that orbits the sun

kleper´s laws: laws that summarize the movements of the planets

the moon in motion

phases of the moon:the shape of lighted part of the moon seen from earth at any time

lunar eclipse v: a blocking  of a viewof the full moon when the moon passes  into Earth´s shadow

solar eclipse : a blocking out of a solar view of the sun when Earth passes throught the moon shadow

tide: the regular rise and fall of the water level along a shortline

Earth and the Sun

rotation . a complete spin on an axis

international date line: the180° line of longitude

standard time zone:a belt 15° wide in longitude in which  all places have the same time

revolution : one complete trip aroun the sun

the tools of astronomers

universe:everything that exist

telescope:a divice that collects light and make distands object apear closser and larger

refraction. the bending of waves as they go from one substance to another

reflection:the bouncing of waves off a surface

wavelength:the distance from one peak to the next on a wave

frequency:the number of waves that pass throught a point in a second

electromagnetic spectrum:waves of light in order by wave lenght

How inclined Planes Work

Inclines Planes:a straight,slantedsurface that is not moved when it is used

screw: an inclined plane wrapped around a central bar.

wedge:one or a combination of inclined planes that is moved when used

compound machine:a combination of two or more machines

efficiency:a ratio of the work done by a machine compared with the work put into the machine