Introduction

When an electric current flows through a wire, a magnetic field is produced around the wire. The magnitude and direction of the field depends on the shape of the wire and the direction and magnitude of the current through the wire.

In this activity, you will examine how the magnetic field is related to both the current through a coil and the number of turns in a coil. A Magnetic Field Sensor will be used to detect the field at the center of the coil. The sensor will also detect the Earth’s field and any local fields due to electric currents or some metals in the vicinity of the sensor, so you will need to account for these fields.

Objectives

  • Use a Magnetic Field Sensor to measure the field at the center of a coil.
  • Determine the relationship between magnetic field and the number of turns in a coil.
  • Determine the relationship between magnetic field and the current in a coil.
  • Explore the Earth’s magnetic field in your room.