The diagram shows the limits of light rays when a large lamp makes a shadow of a small

The first investigation that led to a determination of the speed of light was performed in about 1675 by the Danish astronomer Olaus Roemer. He made careful measurements of the period of 10, a moon about the planet Jupiter, and was surprised to find an irregularity in lo's observed period. While Earth was moving away from Jupiter, the measured periods were slightly longer than average. While Earth approached Jupiter, they were shorter than average. Roemer estimated that the cumulative discrepancy amounted to about 16.5 minutes. Later interpretations showed that what occurs is that light takes about 16.5 minutes to travel the extra 300,OOO,OOO-km distance across Earth's orbit. Aha! We have enough information to calculate the speed of light! a. Write a formula for speed in terms of the distance traveled and the time spent traveling that distance. b. Using Roemer's data, and changing 16.5 minutes to seconds, calculate the speed of light.

a. Which has the longer wavelengths? [radio waves] [light waves]. b. Which has the longer wavelengths? [light waves] [gamma waves]. c. Which has the higher frequencies? [ultraviolet waves] [infrared waves]. d. Which has the higher frequencies? [ultraviolet waves] [gamma rays].

a. Exactly what do vibrating electrons emit? b. When ultraviolet light shines on glass, what does it do to electrons in the glass structure? c. When energetic electrons in the glass structure vibrate against neighboring atoms, what happens to the energy of vibration? d. What happens to the energy of a Vibrating electron that does not collide with neighboring atoms? e. Light in which range of frequencies is absorbed in glass? [visible] [ultraviolet]. f. Light in which range of frequencies is transmitted through glass? [visible] [ultraviolet]. g. 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? h. How does the speed of light compare in water, glass, and diamond?

The Sun normally shines on both Earth and Moon. Both cast shadows. Sometimes the Moon's shadow falls on Earth, and at other times Earth's shadow falls on the Moon a. The sketch shows the Sun and Earth. Draw the Moon at a position for a solar eclipse . b. This sketch also shows the Sun and Earth. Draw the Moon at a position for a lunar eclipse.

The diagram shows the limits of light rays when a large lamp makes a shadow of a small object on a screen. Make a sketch of the shadow on the screen, shading the umbra darker than the penumbra. In what part of the shadow could an ant on the screen see part of the lamp?