[B] Earthquakes generate two sorts of waves in rock, shear or S waves which travel at about 4.5 km/s and pressure or P waves traveling at about 8 km/s. (1) After one such quake, a seismograph station picks up the S wave 3.0 minutes after the P wave. How far away was the source, or epicenter, of the earthquake? |

If a spring is displaced by 20cm from its equalibrium point by 200N, how much will it be displaced by a 400N force?

1) If you want to know the speed of a long-wavelength wave (e.g. tsunami or tide), you can use the shallow-water wave velocity equation   v=gd   where g is acceleration due to gravity (~10 m/s2), d is water depth (in meters), and v = speed (in meters per second).   a) Calculate the speed of a tsunami (in meters per second), assuming an average ocean depth of 4000m.   b) Convert the speed of a tsunami from meters per second to meters per hour (note that 1 hr = 3600 seconds).   c) Convert the speed of a tsunami from meters per hour to miles per hour (note that 1 mile = 1600m).

At sea level, there are two corks that 90cm apart each other. Both of them rise and fall with sea level 40 times in 20second. If one of the cork at the top of sea wave and the other one at the valley of the wave(bottom),there is one hill between two corks, then calculate the wave period (T)and (v)!