Question

A bar magnet is attached solidly to a frictionless surface and its length is aligned with the x axis.To the right of the first magnet a short distance away is a second bar magnet with its center placed on the x axis and its length perpendicular to the x axis.The second magnet is free to move.Once placed in position at rest,which best describes the initial motion of the second magnet?
a. The magnet will move away from the fixed magnet.
b. The magnet will not move.
c. The magnet will move toward the fixed magnet.
d. The magnet will start to rotate.

Answer 1

Answer:

the correct answer is D

Explanation:

For this exercise we must remember that the poles of the same if not repel each other and the poles of different signs attract.

With this, let's analyze the situation presented.

The two magnets are perpendicular, with the second magnet to the right of the first.

We have two cases:

* first magnet with the north pole to the right

  If the north of the second magnet is upwards there is a repulsion and the south pole of the second magnet there is an attraction with the north pole of the first magnet, so it would have a force that has to rotate the second magnet.

The force with the south pole of the first magnet that is at a greater distance is less, so the resultant of force is determined by the nearest poles.

If the poles of the second magnet are reversed, that is, the South pole up and the North pole down, the same result is obtained, but with a twist in the opposite direction.

* first magnet with the south pole to the right

    Repels with the south pole of the second magnet and attracts with the north of the second magnet

therefore in both possibilities the second magnet acquires a rotational movement

Consequently the correct answer is D