The Old North Church: During the American Revolution, Paul Revere instructed a friend to signal him of the approach of the British army. His friend was to use lanterns in the North Church in Boston, Massachusetts: "one if by land, and two if by sea." Paul Revere would watch for the signal from Charlestown, across the river. How far apart did the lanterns have to be placed in order for Paul Revere to reliably distinguish one lantern from two? Suppose the Old North Church in Boston was about 3.6 km from Paul Revere's spot in Charlestown. Assume the diameter of Paul Revere's pupil was about 4.4 mm. You may treat the lanterns as point sources. Assume the effective wavelength of light from each lantern was approximately 642 nm, and the total power output of a lantern was 65 W.

1, What is the diameter, in meters, of the earth's orbit around the sun? Written in scientific notation, the diameter is________ times 10 to the power of_____ meters. 2, According to Roemer, about how many seconds does it take light to travel across the diameter of the earth's orbit? Do NOT include units of measure. 3, How do these two quantities determine the speed of light? 4, When ultraviolet light shines on glass, what does it do to electrons in the glass structure? 5, When energetic electrons in the glass structure vibrate against neighboring atoms, what happens to the energy of vibration? 6, What happens to the energy of a vibrating electron that does not collide with neighboring atoms? 7, How is the speed of light in glass affected by the succession of time delays that accompany the absorption and re-emission of light from atom to atom in the glass? 8, When looking at a shadow, the_________  is darker than the __________ 10, How does the speed of light compare in water,…

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A light wave and sound wave travelling through air both have the same frequency (4000 Hz). Which wave has the bigger wavelength, or are they the same? Explain. (Sound waves travel through air at 340 m/s)