Using the java applet, change the wavelength (starting with a short wavelength and increasing it), run the simulation, and record the results in the chart below. In this simulation, the wavelength (l) is given as "distance". The period (T) is given as "time". You must calculate the frequency (n).

1. What happens to frequency as the wavelength increases?

2. What do you notice about the speed of light in each trial?

3. Show how the equations c=d/t and c=lf are the same.

4. If the frequency of WCYY is 93.9 Mhz (mega = 10⁶), what would be the wavelength of these radio waves?

Travel Time From Earth

5. A light year is the distance light travels in a year. How many kilometers are in a

a. light year (give your answer in scientific notation)? b. light minute? c. light second?

6. Calculate the times to travel to each of the following destinations from the earth, via jet, rocket and sunbeam. Assume for the planets, that the planet is along a line through the sun and the earth on the same side of the sun (distance from earth would be given by the average radius of the planet's orbit minus the average radius of the earth's orbit). The Nine Planets website can help you find this information. Show your calculations on a separate sheet of paper and use scientific notation where appropriate.

destination	distance from Earth	Jet (1000 km/h)	Rocket (42,000 km/h)	Sunbeam (300,000 km/s)
Moon	km	days	hr	sec
Sun	km	years	months	min
Mercury	km	years	months	min
Venus	km	years	months	min
Mars	km	years	months	min
Jupiter	km	years	years	min
Saturn	km	years	years	hr
Uranus	km	years	years	hr
Neptune	km	years	years	hr
Pluto	km	years	years	hr
Alpha Centauri	4.2 light years	years	years	years
Sirius	8.4 light years	years	years	years
Pleiades Cluster	400 light years	years	years	years
Crab Nebula	4000 light years	years	years	years
Center of the Milky Way	38,000 light years	years	years	years
Andromeda Galaxy	2.2 X 106 ly	years	years	years

7. Fill in the blanks in the following paragraph:

The table above is much more than a chart of travel time, it represents a glimpse into the past. When you look into the night sky you are looking into the history of the universe. The sunlight that shines on us is ______ minutes old when it reaches Earth. Sunlight reflected from Pluto takes ______ hours to reach the astronomer's telescope. When the light of Sirius hits your eye, those photons have been traveling for over ______ years through space. This means you are seeing that star not as it is tonight but as it was over ______ years ago. And most of the stars we see in the sky are hundreds or thousands of light years away. The Andormeda galaxy, at a mere ______ million light years, is truly a next door neighbor. All of the other galaxies are millions upon millions of light years distant. And that's how big the universe is.