Question

Ms. Rivera is demonstrating an experiment that includes the use of a compass. A compass has a small magnet that rotates to align with Earth's magnetic field. This small magnet of the compass is called a needle. The model below shows the experiment that Ms. Rivera is demonstrating.



What will most likely happen to the compass needle when the switch is closed and the circuit parts are connected to the battery?
A.
It will turn around once because the completed circuit reverses Earth's magnetic field.
B.
It will remain stationary because there are no magnetic materials included in the circuit.
C.
It will point toward the batteries because they are the only circuit part that can be magnetic.
D.
It will move because the current in the completed circuit will induce a magnetic field.

Answer 1

D.

When the switch closes current flows in the circuit and that current produces a magnetic field. The compass needle (a small magnet) responds to the local magnetic field, so it will deflect to align with the combined field from the current and Earth's field. The battery itself is not the cause.