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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A) Neutrinos travel faster than photons. B) Neutrinos are easier to detect than photons. C) Neutrinos are produced in the explosion before photons. D) Neutrinos are emitted from the outer part of the star; photons come from the core. E) Neutrinos escape from the star quickly because they hardly interact with matter; photons are delayed by interactions with matter.
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.
The Roche limit is the point at which
A) the mass of an object classifies it as a moon. B) a moon orbiting a planet experiences synchronous rotation. C) the external tidal forces on an object are strong enough to be felt by the object. D) the external tidal forces on an object become greater than the internal forces that hold it together. E) the internal forces that hold an object together weaken so that the object falls apart.
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.