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What provides the centripetal force for planets and satellites?
Gravity is the force pulling them together
Bigger the masses, bigger force of gravity
As distance between planets increases, gravity decreases
Orbit of planets are eclipses (slightly squashed circles) with sun at focus
Gravitational force provides centripetal force which allows bodies to maintain circular orbits
Further away orbiting body is, longer it takes to complete orbit
To stay in orbit at particular distance, smaller bodies must move at a particular speed round
Communicators such as satellites are put into geostationary orbit above the equator.
What do mirrors and lenses do to light?
Normal is a construction line perpendicular to the mirror/surface at the point of incidence
Angle of incidence=angle of reflection