Write an expression for the magnitude of the force T that the string exerts on the ball. Assume that the values of q and Qare positive. Express your answer in terms of the variables q, m, Q, r, and appropriate constants.

Alightning strike consists of charge moving from a cloud to the ground . in one particular case, the electrons in a lightning strike are confined to travel within a radius of 1.5 m and to move at a speed of 5.0 x 10 m/s. if the density of electrons in the strike is 10'15 electrons/m what current is carried by the lightning ?

Jessie ran 5000 meters from the cops and an average speed of 6 meters / second before he got caught . how long did he run?

An electromagnet is a device in which moving electric chargers in a coil of wire create a magnet. whats one advantage of using electromagnetic in devices