Contrasting the doppler effect with shock waves, the one that requires the faster source is?

An artificial satellite circles the earth in a circular orbit at a location where the acceleration due to gravity is 6.03 m/s^2. determine the orbital period of the satellite.

What is the primary force that suspension bridges use cables to hold their spans up? a. tension force b. resistance force c. normal force d. elastic force e. applied force

If a simple machine reduces the strength of a force, what must be increased?