Question

5 in a computer simulation, noni moves a magnet (magnet 1) away from another magnet (magnet 2) that cannot move. which statement accurately describes the change in potential energy? a the potential energy does not change because the magnets in the system do not change. b the potential energy decreases because magnet 1 moves in the same direction as the magnetic force. c the potential energy decreases because magnet 1 moves against the magnetic force. d the potential energy increases because magnet 1 moves against the magnetic force.

Explanation:

• When a magnet (Magnet 1) moves against the magnetic force (in this case, moving away from Magnet 2 which is fixed), work is done on the system.
• According to the principle of potential energy in magnetic systems, when work is done against the magnetic force, the potential energy of the system increases.
• Option a is incorrect because potential energy is related to the position of the magnets (due to the magnetic force - position interaction), not just the magnets themselves.
• Option b is wrong because if Magnet 1 moved in the same direction as the magnetic force, potential energy would decrease (work done by the magnetic force), but here it's moving away (against the force in a general sense of magnet - magnet interaction where moving apart when there is an attractive or repulsive force consideration, but in terms of force - displacement relation for potential energy change: \(W =-\Delta U\), \(W = F\times d\times\cos\theta\). If \(\theta = 180^{\circ}\) (moving against the force), \(W=- Fd\) and \(\Delta U=Fd\)).
• Option c is incorrect as moving against the force leads to an increase in potential energy, not a decrease.

Answer:

d. The potential energy increases because Magnet 1 moves against the magnetic force.