There are two basic forms of wave motion, for mechanical waves. These are longitudinal and transverse waves.
The two motions that Earth makes are rotations and revolutions.
No, it is two.
revolution and rotation
Rotation and Revolution.
syncronized
Velocity and gravity (movement around the Earth and the gravity of the Earth pulling on it).
Two
revolution anad rotation
Two are needed at each end of the prism
It moves two ways if that what you are asking.
Rotation and Revolution.
Rotation and Revolution.