INQUIRY BASED MUSEUM EXHIBITS

1st Semester, 2012

 

Our exhibit is an electric and acoustic guitar in one. We are demonstrating how the magnetic pickups amplify the steel string (a string one might find on an electric guitar) and not the nylon string. Visitors will be able to pluck each string and formulate their own ideas about why the nylon string’s sound is not amplified. We will also be demonstrating how different types of pickups affect the sound of the string. We will attach a humbucker and a single coil pickup, both connected to a switch. Visitors will be able to flip the switch causing either the single coil, the humbucker, or both at once to transfer electricity to the output jack.



Pickups are electromagnets. They consist of a bar magnet and copper wire. The wire is wrapped around the magnet thousands of times. The copper wire acts like an electric conductor. When electricity is thrown into the mix, there is a magnetic field created around the wire conductor. This magnetizes the metal. The magnetic field can only be maintained while there is electricity flowing through the wire.



​The concept we want to demonstrate is Faraday’s Law of Induction. Faraday’s Law of Induction states that when a magnetic field is interrupted, an electric current is created if it is part of a closed circuit. We wanted to focus on this because it can be found in many everyday things. For instance, an electric guitar.

The magnetic field inside the pickup is being interrupted by the vibrating string. Since the strings are made of aluminum, nickel and copper, the magnets and the string attract. When the string vibrates, the magnetic field in interrupted, causing an electric field to travel through the pickup’s copper wire. The copper wire extends outside of the pickups and attach to the input jack where the guitar cable is plugged in. The cable then conducts the current into an amplifier which amplifies the sound of the vibrating string.