Magnetic domain structure is responsible for the magnetic behavior of ferromagnetic materials like iron, nickel, cobalt and their alloys, and ferrimagnetic materials like ferrite. ... Magnetic domains form in materials which have magnetic ordering; that is, their dipoles spontaneously align due to the exchange interaction.
Batteries supply electrons to the circuit by releasing negatively charged atoms or ions. These ions are produced by the batteries through a chemical reaction that spontaneously occurs within the battery. So the negative end of the battery pushes the ions towards the positive end of the circuit with the help of the voltage. This is why eventually, batteries "run out" when the electrode is used up and the chemical reaction can no longer continue.
Answer:
12 ml
Explanation:
The initial volume in the cylinder is 20 ml
adding the rock adds volume to the cylinder
the new volume is 32 ml .....the increase in volume is the volume of the rock : 32 - 20 = 12 ml volume of rock