Armonk Prep ESR Review Flashcards
(77 cards)
celestial motion
celestial objects change position in the sky over time, from east to west at the same rate along an arc
celestial object
objects that can be seen in the sky that are not associated with earth’s atmosphere
(sun, moon, not rainbows, clouds)
how did our solar system form
- giant interstellar cloud of gas and debris
- gravity makes cloud shrink
- as it shrinks it spins faster and flattens into a disk with a central bulge
- disk of gas and dusk spins around the young sun
- dusk grains clump into planetesimals
- planetesimals collide and connect into planets
what is the celestial sphere
early observers thought there was a “huge sky ball” slowly spinning around a motionless earth
this explained why all of the celestial objects moved in the same direction at the same speed
zenith
the point on the celestial sphere that is right over an observer’s head at any given time
where is polaris located
very close to the north pole
how fast does earth rotate
15 degrees an hour
what is the central line the earth rotates around
the axis of rotation
axis of rotation
a line passing through the north pole, earth’s center, and the south pole
directly aligned with polaris
tilted at 23.5 degrees
what proves earth’s rotation
foucault pendulum, coriolis effect
foucault pendulum
gravity pulls a pendulum only toward earth’s center, if set freely swinging in the absence of any lateral forces, the pendulum should swing on a fixed plane
coriolis effect
as air moves from high to low pressure in the northern hemisphere, it is deflected to the right by the coriolis force
in the southern hemisphere it’s deflected to the left
what causes the length and position of the sun to vary
seasons and latitude
on different days of the year, an observer will see the sun follow different ______ through the sky
paths
how will the way someone views the sun change if they are closer to the equator
they will observe the sun at a higher altitude
meridian
any great circle that passes through both the north and the south poles
what line is at 0 degrees longitude on earth
the prime meridian
what line is at 180 degrees longitude on earth
international date line
the shorter the sun’s daily path is, the shorter the…
period of daylight and lowest altitude
these happens on december 21 (winter solstice)
newtons 3 laws
- a body in motion remains in motion or a body at rest remains at rest, unless acted upon by force (inertia)
- force = mass x acceleration
- for every action, there is an equal and opposite reaction
inertia
the measure of an object’s resistance to change of velocity
inertia is proportional to the _____ of an object
mass
the more massive an object is, is it more or less likely to be resistant to change
the more massive an object is, the greater it’s resistance is to change
acceleration equation
acceleration= net force/mass
