passwella.
Menu

JAMB Physics 1979 Question 26

Question 26

Magnetism

Which of the following statements is correct? The magnetized state of an iron bar can be destroyed completely by

  1. A.heating the bar to a high temperature
  2. B.breaking the bar
  3. C.connecting opposite poles with a small piece of iron
  4. D.placing the bar inside a strong magnetic field
  5. E.none of the above.
Show the answer and explanation

Answer: A (heating the bar to a high temperature)

Explanation

Strong heating makes the atoms vibrate violently and throws the magnetic domains out of line, destroying the magnetism. Breaking the bar just makes smaller magnets.