An electromechanical relay has a coil voltage rating of 5 volts and a coil resistance of 150 ohms. However, you desire to energize this relay with a 12 volts car battery. You know that a series connected resistor might enable the 5 volt relay coil to be powered by by the 12 volt battery without damage, what size of resistor would be appropriate for the task

A6,600 kg train car moving at +2.0 m/s bumps into and locks together with one of mass 5,400kg moving at -3.0m/s. what is their final velocity? +0.50 m/s -1.0 m/s +2.5 m/s -0.25 m/s

Electroplating is a way to coat a complex metal object with a very thin (and hence inexpensive) layer of a precious metal, such as silver or gold. in essence the metal object is made the cathode of an electrolytic cell in which the precious metal cations are dissolved in aqueous solution. suppose a current of 480.ma is passed through an electroplating cell with an aqueous solution of agno3 in the cathode compartment for 46.0 seconds. calculate the mass of pure silver deposited on a metal object made into the cathode of the cell. round your answer to 3 significant digits. also, be sure your answer contains a unit symbol. ×10μ

What is the orbital period of a spacecraft in a low orbit near the surface of mars? the radius of mars is 3.4×106m.