What condition is necessary for two bodies that are in physical contact with each other to be thermal equilibrium?

Sound waves are mechanical waves in which the particles in the medium vibrate ina direction parrallel to the direction of energy transport. what is another name of the type of wave that transfers energy in this way?

When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

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.