Speed of Light The speed of light is c = 3.0 108 m/s. This is quite fast. In this problem, you will explore just how fast.

Speed of LightThe speed of light is c = 3.0 · 108 m/s. This is quite fast. In this problem, you will explore just how fast. a) Many communications satellites orbit the earth in geostationary orbits. (They appear to remain in the same positions in the sky for observers on the earth’s surface.) If such a satellite orbits at a height of 40,000 km, estimate the time delay in a cell phone conversation due to the time it takes light to travel from onephone to the other via the satellite. b) The moon orbits the earth at an average distance of 3.8 · 108 m. About how long did it take NeilArmstrong’s famous transmission — “That’s one small step for man, one giant leap for mankind” — to reach Houston?c) The orbital radius of the earth is about 1.5 · 1011 m. If the sun vanished, how long would it be before anyone realized?d) A light year is the distance light travels in one year. How far is this, in meters? In miles?e) The nearest star to earth is about 4 light years away. The Voyager 2 space probe — the fastest man made object in the universe — is moving away from the sun with a speed of about 17.5 km/s. How long will it take Voyager 2 to travel 4 light years?