The Magnetic Field of the Earth

Figure 1

In this experiment we explore the magnetic field of the Earth.

We determine the magnitude and the direction of Earth’s magnetic field, and its inclination.

einstein™Tablet+ with MiLAB or Android/iOS Tablet with MiLAB and einstein™LabMate 

Magnetic Field sensor



Compass

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Protractor



Plumb (or level)

1.

2.

3.

4.

5.

Launch MiLAB ( ).

Connect the Magnetic Field sensor sensor to one of the ports on the einstein™Tablet+ or einstein™LabMate.

Set the sensor switch to the high sensitivity range.

Use the pull down menu in the Current Setup Summary window to select the Magnetic Field sensor.

In the Current Setup Summary window choose Full Setup and use the table below to set up the experiment. Make sure that only the Magnetic Field sensor is selected under Measurements.

Program the sensors to log data according to the following setup: Magnetic Field Sensor

Magnetic ď‚ą0.2 mT (mT)

Rate:

10/sec

Duration:

50 Sec

1.

Find a place in your laboratory as far from ferromagnetic materials and magnetic fields as possible. You will need enough space to rotate your body 360 degrees with your arm outstretched.

2.

Select Run (

3.

Hold the sensor in your hand and extend your arm to fully outstretched. Rotate your body and the sensor, making a full circle staying within a horizontal plane. Make sure to hold the sensor so that you maintain a constant distance from the ground.

Find the angle for which the readings are maximal and remain in this position (see Figure 2). Now rotate the sensor a full circle in a vertical plane.

Magnetic Field (mT)

4.

) to begin recording data.

Figure 2

For more information on working with graphs see: Working with Graphs in MiLAB. 1.

2.

Zoom in on the data acquired during the vertical circling.

Use two cursors to select the maximum and minimum in this part of the graph. The difference between these points will be now displayed in the information bar below the graph window. That should be twice the magnitude of the vertical component of the magnetic field of the Earth.

3. Write this value down in your notebook.

4. Zoom in on the data acquired during the horizontal circling.

5. Use two cursors to select the maximum and minimum in this part of the graph. This difference between theses points will be now displayed in the information bar below the graph window. That should be twice the magnitude of the horizontal component of the magnetic field of the Earth.

6. Write this value down in your notebook.

7. Use these two results to find the angle of inclination of the magnetic field of the Earth.

Write the angle down in your notebook.