The Dynamo Theory holds that:
A) lightning plays a major role in generating our magnetic fields.
B) any other planet of similar density will also have a strong magnetic field.
C) the Earth's core, like Mercury's, is now a solid, rigid bar magnet.
D) magnetic fields are generated by rapidly spinning, fluid magnetic interiors.
E) the Earth's magnetic field must switch polarities every few million years.
D
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How many tidal bulges "move" around Earth daily?
a. Two b. Six c. One d. Four
Two observers will always agree on
A. the speed of light. B. the mass of cosmic ray muons. C. the charge of cosmic ray muons. D. the lifetime of cosmic ray muons.
Impulse: A 0.24 kg blob of clay is thrown at a wall with an initial horizontal velocity of 16 m/s. If the clay comes to a stop in 91 m/s, what is the average horizontal force on the clay due to the wall?
A. 42 N B. 26 N C. 35 N D. 51 N
If the Sun passes almost in front of the center of our Milky Way Galaxy, it does so
A) once a year. B) once a day. C) only in 2012, at the end of the Mayan calendar. D) once a month.