Select True or False for each of the following statements regarding magnetism, a
ID: 1259423 • Letter: S
Question
Select True or False for each of the following statements regarding magnetism, and the earth's magnetic field "B."
The direction of B is indicated by the N pole of a magnetic needle .
The magnitude of earth's B is about 1E-4 Tesla.
For a bar magnet, the B - lines exit through the N pole and return through the S pole .
The vector B acts only on charges at rest.
The earth's B lines are parallel to the earth's surface at all points.
B does work on a charge only when the charge has a velocity component perpendicular to B.
Unlike magnetic poles attract.
Explanation / Answer
True Magnetic field lines outside of a permanent magnet always run from the north magnetic pole to the south magnetic pole. Therefore, the magnetic field lines of the earth run from the southern geographic hemisphere towards the northern geographic hemisphere.
The direction of B is indicated by the N pole of a magnetic needle . TRUE
your answer is not correct. B value at any point due to a bar magnet will have different direction depending on the location. Of course when the point is on axial line then it will parallel to the magnetic moment of the bar magnet. Magnetic moment is a vector whose direction is always directed from South to North within the bar.
The magnitude of earth's B is about 1E-4 Tesla. FALSE
You are right. This too changes from place to place.
For a bar magnet, the B - lines exit through the N pole and return through the S pole . TRUE
YOurs is correct.
The earth's B lines are parallel to the earth's surface at all points.FALSE
Once again you are right
The vector B acts only on charges at rest. FALSE
Yes you are right. Because there will be no inflence on the stationary charge by any magnetic field.