Characteristics of Waves: An earthquake generates three kinds of waves: surface waves (L-waves), which are the slowest and weakest, shear (S) waves, which are transverse waves and carry most of the energy, and pressure (P) waves, which are longitudinal waves and are the fastest. The speed of P waves is approximately 7 km/s, and that of S waves is about 4 km/s. People do not generally feel the P waves, but animals seem to be sensitive to them. If a person reports that her dog started barking 20 seconds "before the earthquake," then approximately how far was the origin of the earthquake?
A. 100 km
B. 200 km
C. 300 km
D. 400 km
E. 500 km
Answer: B
You might also like to view...
Mass on a Spring: A mass on a spring undergoes SHM. When the mass passes through the equilibrium position, which of the following statements about it are true? (There could be more than one correct choice.)
A. Its acceleration is zero. B. Its speed is zero. C. Its elastic potential energy is zero. D. Its kinetic energy is a maximum. E. Its total mechanical energy is zero.
Tidal forces are very important to the Algol system today, but were not important when both stars were still on the main sequence. Why not?
A) Main-sequence stars in a system like the Algol system are small compared to their physical separation. B) Main-sequence stars are too big to be affected by tidal forces. C) Main-sequence stars are too massive to be affected by tidal forces. D) Main-sequence stars are unaffected by tidally-induced mass transfer.
If the insolation upon a flat plate collector is 800 Btu/ft2/day, how large must the collector be to provide 30,000 Btu/hr of thermal energy for an entire day? Take the efficiency of the collector to be 50%
a. 150 b. 750 c. 1800 d. 4000 e. 7200 ft2
Consider a situation where a skater pulls her arms inward, causing her rotation rate to speed up. Linear momentum is not conserved
Indicate whether the statement is true or false