Outside a bar magnet, do the field lines run from north to south, or from south to north?
Held level with a bar magnet's middle, a steel paper clip feels only a weak force. Held near either pole, it feels a strong one. The field drawing already says so, in the gaps between the lines.
Field lines carry a second piece of information, and it is not written on any one line. It sits in the spacing.
Here is the bar magnet's field again. Near the poles, the lines bunch up. Out at the sides, the same lines spread apart.
A paper clip held near a pole sits where the lines are close together. The force on it is strong. The same clip held out at the side sits where the lines are far apart. The force on it is weak.
In a drawing of a star's field, where is the field stronger: close to the star, or far from it?
Close to the star, the drawn lines sit closer together.
Where field lines are closer together, the field is stronger.
The field is stronger close to the star.
Where does the sphere's field push a charged bead the hardest?
The same reading runs in reverse: where the lines sit farther apart, the field is weaker.
In the drawing, the lines sit closer together next to the asteroid than far away. Kofi says the field is stronger next to the asteroid. Is Kofi correct?
One care with the reading. How long the artist draws each line means nothing. Only the spacing between lines carries strength.
June says a field is stronger wherever each drawn line is longer. Is June correct?
The field next to a charged sphere is stronger than the field far from it. Which feature of the drawing shows that?
In the drawn field, the lines are evenly spaced everywhere. Compare the force on one charged bead at the top of the drawing and at the bottom.
Which statement about reading strength from a field drawing is correct?