What is the average value of the magnitude of the Poynting vector 
at 1 meter from a 100-watt lightbulb radiating in all directions?
A. 1 W/m2
B. 4 W/m2
C. 2 W/m2
D. 8 W/m2
E. 12 W/m2
Answer: D
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The mass of a galaxy's central black hole is proportional to the mass of its _______________
Fill in the blank(s) with correct word
Multiple-Object Accelerating Systems: Three boxes rest side-by-side on a smooth, horizontal floor. Their masses are 5.0 kg, 3.0 kg, and 2.0 kg, with the 3.0-kg mass in the center. A force of 50 N pushes on the 5.0-kg box, which pushes against the other two boxes. What magnitude force does the 5.0-kg box exert on the 3.0-kg box?
A. 0 N B. 10 N C. 25 N D. 40 N E. 50 N
Long-period comets are believed to come from the ______________
Fill in the blank(s) with correct word
An automobile moving along a straight track changes its velocity from 40 m/s to 80 m/s in a distance of 200 m. What is the (constant) acceleration of the vehicle during this time?
a. 8.0 m/s b. 9.6 m/s c. 12 m/s d. 6.9 m/s e. 0.20 m/s