Vật dao động điều hòa theo phương trình: x = 4cos(8Ttt - T/6)cm. Thời gian ngắn nhất vật đi từ -2cm theo chiều dương đến vị trí có li độ 2 cm theo chiều dương là:

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.