Question

Discuss how the accuracy of a compass needle in showing the true direction of north can be affected by the magnetic field due to currents in wires and appliances in a residential building.

Short answer

In summary, the accuracy of a compass needle in showing the true north direction can be affected by magnetic fields generated by electrical currents in wires and appliances within a residential building. These magnetic fields can cause deviations from the true north direction when the compass is located close to the source generating the magnetic field. To minimize the effect of these magnetic fields, it is important to keep the compass away from electrical devices and wiring, turn off appliances when not in use, and use a compass with higher magnetic sensitivity for improved accuracy.

Step-by-step solution

Understanding how a compass needle works

A compass needle works by aligning itself with Earth's magnetic field. The compass needle, being a small magnet itself, aligns with the magnetic field lines such that its north pole is attracted to Earth's magnetic south pole (which is close to the geographic North Pole) and its south pole is attracted to Earth's magnetic north pole (which is close to the geographic South Pole).

Identifying sources of magnetic field in a residential building

Various electrical appliances and wiring within a residential building can generate their own magnetic fields, which can impact the accuracy of a compass needle. Some common sources of magnetic fields in residential buildings are: 1. Electrical wiring in walls, floors, and ceilings 2. Electronic devices like TVs, computers, sound systems, and mobile phones 3. Household appliances like refrigerators, air conditioners, and washing machines 4. Power transformers and distribution boxes. These magnetic fields can cause a compass needle to deviate from the true north direction when it is located close to the source generating the magnetic field.

Describing the effect of magnetic fields on compass needle

The magnetic fields generated by electrical currents in a residential building can cause the compass needle to deviate from the true north direction because they interact with the Earth's magnetic field. When a compass needle is near a source of an external magnetic field, it experiences the combined force of Earth's magnetic field and the external magnetic field, causing the needle to align with the resultant magnetic field, which deviates from the Earth's magnetic field. This deviation causes the compass needle to point in a direction different from the true geographic north.

Discussing ways to minimize the effect on compass needle

There are several ways to minimize the effect of magnetic fields generated by electrical currents in a residential building on a compass needle: 1. Keep the compass away from electrical devices and wiring as much as possible. This includes keeping the compass away from walls, floors, and ceilings where electrical wires are usually installed. 2. Turn off electrical appliances when not in use. This can help reduce the magnetic field generated by these devices. 3. Use a compass with a higher magnetic sensitivity. These compasses can better distinguish between Earth's magnetic field and external magnetic fields, improving their accuracy in showing the true north direction.