An iron bar can be made magnetic when
its magnetic domains line up
it rotates its poles to line up with another magnet
it spins its electrons in different directions

Quantum mechanics applies to subatomic, atomic, nanometer-size, and micrometer-size systems. nanometer, micrometer, and kilometer-size systems. atomic, nanometer-size, and micrometer-size systems. subatomic, atomic, and nanometer-size systems.

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer

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