On December 26, 2004, a great earthquake occurred off the coast of Sumatra and triggered immense waves that killed hundreds of thousands of people. Satellites observing these waves from space measured 800 km from one wave crest to the next and a period between waves of 1.0 hour. What was the speed of these waves in m/s and km/h?

Question

On December 26, 2004, a great earthquake occurred off the coast of Sumatra and triggered immense waves that killed hundreds of thousands of people.  Satellites observing these waves from space measured 800 km from one wave crest to the next and a period between waves of 1.0 hour.  What was the speed of these waves in m/s and km/h?

I know the answers are 220 m/s and 800 km/h, but how do I get the answers?

bobpursley · Accepted Answer

frequency*wavelength= velocity velocity= 1/3600sec * 800E3m=220m/s