what is the equation of motion for a negative charge rotating around a postive charge in a magnetic field

An astronomer at the equator measures the doppler shift of sunlight at sunset. from this, she calculates that earth’s tangential velocity at the equator is 465 m/s. the centripetal acceleration at the equator is 3.41  10 2 m/s 2 . use this data to calculate earth’s radius.

Ammonia enters the expansion valve of a refrigeration system at a pressure of 10 bar and a temperature of 18oc and exits at 6.0 bar. the refrigerant undergoes a throttling process. determine the temperature, in oc, and the quality of the refrigerant at the exit of the expansion valve.

Which atomic model was proposed as a result of j. j. thomson’s work?