Two radio antennas are 10 km apart on a north-south axis on high mountain tops at the seacoast. The antennas broadcast identical AM radio signals,
in phase, at a frequency of 4.70 MHz. A steamship, 200 km offshore, travels toward the north at 15 km/h and passes east of the antennas. A radio on board the ship is tuned to the broadcast frequency. The reception of the radio signal on the ship is a maximum at a given instant. How much later until the next occurrence of maximum reception? (c = 3.00 × 108 m/s)
A) 5.1 min
B) 3.8 min
C) 6.4 min
D) 7.7 min
E) 8.9 min
A
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The Roche limit is the point at which
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Two tiny beads are 25 cm apart with no other charges or fields present. Bead A carries 10 µC of charge and bead B carries 1 µC. Which one of the following statements is true about the magnitudes of the electric forces exerted on these beads?
A) The force exerted on A is 10 times the force exerted on B. B) The force exerted on B is 10 times the force exerted on A. C) The force exerted on A is exactly equal to the force exerted on B. D) The force exerted on A is 100 times the force exerted on B. E) The force exerted on B is 100 times the force exerted on A.
One of the fundamental ideas in the development of quantum mechanics was that
A. no two particles can have the same energy. B. all particles have wave properties. C. electrons and protons are the only particles D. all particles are formed by the interaction of electromagnetic waves. with mass.