Planet B has a period of 51 days and a radius of 7 x 10^6​ ​ m. Planet A has a radius of 9.0 x 10^6​ m . Calculate the period of Planet A.

Three point charges, two positive and one negative, each having a magnitude of 20 μc are placed at the vertices of an equilateral triangle (30 cm on a side). what is the magnitude of the electrostatic force on the negative charge

Atomic nuclei of almost all elements consist of

When is a current produced? when the terminals of an electrochemical cell are connected by a wire if the electric circuit is opened in an electrochemical cell if the electrolyte is removed from an electrochemical cell when the electrodes are reversed in an electrochemical cell