Applications to Astronomy: The cosmic background radiation corresponds to a temperature of about
A. 1.4 K.
B. 2.7 K.
C. 8.0 K.
D. 20 K.
Answer: B
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Projectile Motion: A projectile leaves the ground at 150 m/s and reaches a maximum height of 0.57 km. If there was no air resistance, at what angle above the horizontal did it leave the ground?
Fill in the blank(s) with the appropriate word(s).
How are Cepheids and RR Lyrae stars different?
What will be an ideal response?
Recall that Hubble's law is written v = H0d, where v is the recession velocity of a galaxy located a distance d away from us, and H0 is Hubble's constant. Suppose H0 = 65 km/s/Mpc
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A block of mass M slides down a frictionless plane inclined at an angle ? with the horizontal. The normal reaction force exerted by the plane on the block is directed
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