Explain how to use a compass.

To use a compass, follow these steps:

1. Hold the compass flat in the palm of your hand with the direction of travel arrow pointing away from you.
2. Rotate the compass housing until the orienting arrow lines up with the north arrow on the compass housing.
3. Hold the compass level and steady, and turn your body until the red end of the magnetic needle points to the "N" on the compass housing.
4. Now, you are facing north. To determine other directions, simply turn your body while keeping the compass level and the red end of the needle pointing to the "N" on the housing.
5. To find a specific direction, such as east or west, simply rotate the compass housing until the desired direction aligns with the orienting arrow.
6. Remember to keep the compass away from any magnetic objects, such as cell phones or metal objects, as they can interfere with the accuracy of the compass reading.

Materials:

- Compass

Steps:

1. Orient the Compass:

- Hold the compass on a flat surface.
- Align the compass's magnetic needle with the Earth's magnetic field. The red or north-pointing end of the needle should point towards the north.

2. Determine the Cardinal Directions:

- The arrow or "N" mark on the compass's bezel (the outer ring) indicates north.
- The other cardinal directions (east, south, and west) are marked 90 degrees counterclockwise from north.

3. Find True North:

- Most compasses have a declination adjustment screw or gauge.
- Adjust the screw or gauge to account for the difference between magnetic north and true north in your location. (See below for how to find this difference.)

4. Measure Angles:

- The bezel of the compass is marked with degrees, usually from 0 to 360.
- Align the index line (typically a small triangle or mark) on the compass case with the object you want to measure the angle to.
- Read the angle on the bezel where the index line intersects the object's line of sight.

5. Determine Magnetic Declination:

- Magnetic north does not always align exactly with true north due to the Earth's magnetic field.
- To find the local magnetic declination:
- Use an online declination calculator.
- Consult a USGS topographic map for the area.
- Measure the angle between magnetic north and true north using a map and protractor.

Tips:

- Hold the compass steady and level for accurate readings.
- Avoid holding the compass near magnetic objects that can interfere with its accuracy.
- Calibrate your compass regularly by pointing it towards the Earth's magnetic poles and adjusting the declination accordingly.
- Consider using a map and protractor for more precise angle measurements.