A change in the frequency of a sound, light, or other wave caused ...

[bobypop]

A change in the frequency of a sound, light, or other wave caused by movement of the wave's source relative to the observer is known as the _______________.
 Fill in the blank(s) with correct word

Question 2

Some geologists believe that we could reduce the threat of earthquakes by pumping liquids into locked segments of active faults. What is the theory behind this belief?

[cadimas]

Answer to Question 1

Doppler effect

Answer to Question 2

Some geologists think that by pumping liquids into locked segments of active faults, they can generate small- to moderate-size earthquakes. These earthquakes would relieve the buildup of pressure along a fault and thus prevent very large earthquakes from taking place.