Questions 1. Can you explain the purpose of the iron fillings?

2. Is the force constant along a magnetic field line?

3. Do lines of force cross each other? Explain.

4. Why did you point the magnet's South Pole toward earth's north?

5. If you want to store two bar magnets, what orientation should they have with respect to each other so as not to weaken their magnetic fields?

Answers:

1. Iron filings are very small elongated grains of iron. The purpose of iron filings is to produce a "picture" of magnetic field. If there are enough grains , iron filings can give a very detailed representation of the magnetic field. They align themselves along the magnetic field lines.

2. Yes, force is constant along a magnetic field line.

3. No,lines of force don't cross each other. Two lines of force crossing each other would mean that at the crossing point the magnetic force is acting in two direction which can,t be true, Force due to magnetic object will be only in one direction at a point. The direction of magnetic field will be only in one direction at a time,

4. Because opposite poles attract each other, magnet's south pole will get attracted towards earth's north pole.

5. To store two bar magnets so that they don't weaken their magnetic field, we need to store them opposite orientation. We generally store bar magnets with unlike poles opposite and pieces of soft iron (keepers) across the ends.