Four compasses are placed around a wire, as shown. what is the best conclusion that can be drawn? a) a current flows up the wire. b) a current flows down the wire. c) a current flows, but its direction cannot be known. d) a current does not flow in the wire.

The best conclusion that can be drawn is that D) A current does not flow in the wire

The correct answer is (D).

Explanation:

If the current is flowing in the wire then the compass shows the deflection due to the magnetic field around the current flowing wire.

In the given problem, four compasses are placed around a wire, as shown in the given figure. The compass is not showing any deflection. It means that there is no magnetic field around the wire. It can be concluded that the current is not flowing in the wire.

Therefore, the correct option is "A current does not flow in the wire".

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