How do we specify the location of a star on the celestial sphere?
We use two coordinates called right ascension and declination to specify a star's
position.
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An object consists of a rod (of length 3.0 m and negligible moment of inertia) to which four small 2.0-kg masses are attached, one at each end and one at each point on the rod 1.0 m from each end. (The masses are one meter apart.) The moment of inertia of this object about an axis perpendicular to the rod and through one of the end masses:
a. is 28 kg•m2. b. is 12 kg•m2. c. is 4 kg•m2. d. cannot be uniquely determined until it is stated which inner mass the axis goes through.
A quanton is moving in a classically allowed region. If the quanton would classically have at point xA twice the kinetic energy it would have at point 
, how would the wavelengths of an energy eigen function of the quanton compare at these points?
A. ?A = 2?B
B. ?A = 
?B
C. ?B = ?A
D. ?B = 2?A
E. ?B = 4?A
Thin Lenses: A 14-mm tall postage stamp is 4.0 mm from a converging lens. If the image of the stamp is 4.0 mm tall, how far is it from the lens?
A. 14 mm B. 8.7 mm C. 1.4 mm D. 1.1 mm
Why is it so difficult to make a direct image of a planet around another star?
What will be an ideal response?