A single-engine helicopter has two rotors; a main rotor and a tail rotor. The main rotor has a diameter of 14.6 m and rotates at the rate of 480 rev/min while the tail rotor with a diameter of 1.84 m rotates at 3875 rev/min. What are the speeds, in m/s, of the tips of each rotor

Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.