The number of oscillations that a wave completes per unit of time in called its

The seven sisters, seven stars located more than 400 light-years away in the taurus constellation can be seen here with venus and another constellation, orion. the seven stars stay grouped together but seem to move, like the planet venus. why do stars seem to move like planets in the night sky?

Asatellite with an orbital period of exactly 24.0 h is always positioned over the same spot on earth. this is known as a geosynchronous orbit. television,communication, and weather satellites use geosynchronous orbits. at what distance would a satellite have to orbit earth in order to have a geosynchronous orbit?

Aprotein molecule in an electrophoresis gel has a negative charge.the exact charge depends on the ph of the solution, but 30 excesselectrons is typical. what is the magnitude of the electric forceon a protein with this charge in a 1500 n/c electric field?