Suppose you live at latitude 40°N. Which of the following describes the conditions that make a star circumpolar?
A) Stars are circumpolar if they have declination > +50°.
B) Stars are circumpolar if they have declination > +40°.
C) Stars are circumpolar if they have right ascension > 6 hr.
D) Stars are circumpolar if they have right ascension < 6 hr.
E) No stars are circumpolar at this latitude.
A
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What will be an ideal response?
A rectangular coil lies flat on a horizontal surface. A bar magnet is held above the center of the coil with its north pole pointing down. What is the direction of the induced current in the coil?
A) There is no current in the coil. B) clockwise C) counterclockwise D) Not enough information is provided.
Two children start at one end of a street, the origin, run to the other end, then head back. On the way back Joan is ahead of Mike. Which statement is correct about the distances run and the displacements from the origin?
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