Which is true of magnetic field lines, but not electric field lines?

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

Which describes increasing the efficiency of energy resource

Suppose you hit your hand against the edge of table. using newton’s third law of motion why does my hand hurt? explain