richter
Seismometer (or seismograph) and it measure seismic waves
The science of earthquakes are known as seismology.
Yes. If you are interested only in the magnitude (scalar quantity), you call it "speed"; if you are interested in the vector (magnitude and direction), you call it "velocity".
a seismograph
Seismologists
Epicentre
This instrument is a balance.
Quantity
Amplitude
A Seismologist.
its called the magnitude dumb *ss
The term is "absolute magnitude".