Homework: Note you will sometimes need information that resides elsewhwr in the book like chapters you have read already or in the Appendices! Be Brave Look!

1a) You are driving at 60 miles/hour and you cross the Canadian Border.  Convert your speed to Km/hr.  Convert your speed to km/s. 

2a) What is the  Earth's orbital speed in km/s?
2b) What is the Earth's centripal acceleration?
2c) Calculate the Force of the Gravity between the Sun and the Earth.  How does it compare to the mass of the Earth times the Earth's centripal acceleration calculated in 2b (You are verifying that F does = ma!)

3) Use Newton's law of gravity to calculate the force of gravity between you and the Earth.  Convert your answer from Newton's to pounds using the conversion

									4.45 N = 1 lb

What would you normally call this force.
Peform this same calculation including the conversion for you standing on the Moon,
and on Jupiter.

4) Jupiter's moon Callisto orbits it at a distance of 1.88 million km.  Its orbital period about the planet is 16.7 days.  What is the mass of Jupiter? (assume the mass of Callisto is small compared with that of Jupiter's)

5) What is the wavelength of 100 MHz (FM 100) radio waves

6) According to Wien's law how many times hotter is an object whose blackbody emission spectrum peaks in the Ultraviolet at 2000 angstroms than one which peaks in the Infared at 6500 angstroms?  

7) Normal human body temperature is 37 degrees centigrade. To convert to degrees Kelvin you just add 273 degrees

       										 Kelvin = Centigrade + 273

What is the peak wavelength emitted by a person at this temperature?  In what part of the spectrum does it occur?

8) At what wavelength does a star forming cloud at T = 1000 K radiate most strongly?