Physics 102 (section 002) Introduction to Physics

        This course is about the most important and most accessible ideas of astronomy and physics with some coverage also of chemistry and biology.

       My e-mail address is

       Information about the final exam is near the bottom of this webpage.

        There are three textbooks.  The first is Steven Weinberg's book The First Three Minutes available from Amazon for $12.20 plus shipping.  The second book is Physics for Future Presidents: The Science Behind the Headlines
  by Richard A. Muller (Paperback - Sep 21, 2009, available at Costco for $10.99).  The third book is Israel Rosenfield's DNA for Beginners available (used) from sellers affiliated with Amazon.

       Some websites,,,, Herschel website, Planck website,  MPE website.

       Here are the class notes, which are a work in progress.

       Here's a cool movie of stars orbiting a super-massive black hole (Sgr A*) at the center of our galaxy.   This black hole has a mass about 4.3 million times that of the Sun.  It is about 25,900 light-years away.  ESO astronomers used a
SHARP camera mounted on the NTT telescope in Chile to photograph these stars in near-infrared light and made the movie from those pictures.  At the center of the galaxy NGC 4258, there also is a super-massive black hole; its mass is about 39 million times that of the Sun, and it is 23.5 million light-years away.  
        One light-year is the distance light goes in one year moving at the speed of light, c = 300,000 km/s.  So one light-year is the distance d = 365*24*60*60s*300,000 km/s = 9.5 x 10^12 km, that is, 9.5 trillion km.  The term parsec means 3.26 light-years.

       Here's Katie Richardson-McDaniel's lecture on dark matter.

       Here is Steven Strogatz's discussion of complex numbers.  Here he talks about calculus.

       Here is the mid-term take-home exam.    Here are the answers.

       Here is a link to Professor Nate Lewis's website.   He points out that the planet-wide energy requirements of the world's population are some 15 TW = 15,000,000,000,000 Watts and in forty years will be about 45 TW.   Only two sources of energy can satisfy this need:  coal and solar.  To use coal is to gamble with the planet.  So we should develop solar technology to the point where it can supply 45 TW in 50 years.

       Here is the take-home final exam.  You must put your answers on one of the multiple-choice sheets which I handed out in class on 3 May or on an identical form.  You may turn in your
multiple-choice sheet
during class on Wednesday, 5 May, or at 5:30 pm on 10 May, which is the date of the final exam, or just put it in my mailbox in the Department of Physics & Astronomy on Lomas at Yale.
    Here are the answers.