Physics 2 Laboratory - Electromagnetism

Within the scope of PHYS 104L Physics II Laboratory course, student teams conduct and report several experiments such as Transformer, Biot-Savart Law, Wheatstone Bridge, Magnetic Field Near a Straight Line, Resistance of Conductor Content, Kirchhof's Laws, Ohm's Law, Equipotential Surfaces, Self Induction, Discharge Curve of a Capacitor experiments.

The experiments in the field of electromagnetism are based on the measurement of current, magnetic fields and potential differences using proper tools. These tools are used for the purpose of determining some of the electrical parameters such as resistance, power, inductance and capacitance. Using magnetic field sensors, magnetic field around conductors having various geometries are measured and current-magneticfield relations are obtained. Dependence of magnetic field strength with the distance from the source is also extracted.


1- Transformer
Alternating current (AC) is applied to one of two coils, the primary coil, wounded on a common iron core. The voltage induced in the second coil (named as secondary coil) and the current flowing in it are measured as functions of the number of turns in the coils and the current flowing through the primary coil.

2- Biot-Savart Law
The magnetic field along the axis of wire loops and coils of different dimensions are measured with a teslameter (Hall probe). The relationship between the maximum field and the geometry of the coils providing the magnetic field is investigated and comparison is made between the measured values and theoretical approaches.

3- Wheatstone Bridge
Wheatstone bridge circuit is used to determine unknown resistances. The total resistance of resistors connected in parallel and in series is measured.

4- Magnetic Field Near a Straight Line
A current which flows through conductors produces magnetic field around them. Magnitude of the magnetic field generated by these conductors depends on the current, geometry of the conductor and the distance from it. The magnetic field can be directly measured around the conductors to understand the effect of these parameters.

5- Resistance of a Conductor Content
Resistance of a conducting wire can be measured by measuring the potential drop on it and the current through it. For the wires with known diameter and resistivity, resistances can also be determined theoretically. These results can be compared.

6- Kirchhof’s Laws
Kirchhoff’s laws are verified by measuring current, voltage and resistance in series and parallel circuits. Wheatstone bridge circuit is used to determine unknown resistances more precisely. However, that is a different experiment.

7- Ohm’s Law
Ohm’s law is one of the well-known principle in electricity. If there is a linear relation between the current flowing and the voltage drop on a circuit element, this circuit element is known to obey Ohm’s Law.

8- Equipotential Surfaces Content
Equipotential lines are like contour lines on a map which trace lines of equal altitude. In this case the "altitude" is electric potential or voltage. Equipotential lines are always perpendicular to the electric field lines. In three dimensions, combination of points with the same potential form equipotential surfaces. Motion along an equipotential surface requires no work since the direction of motion is perpendicular to the electric field.

9- Self Induction
A coil is located in a DC circuit. When the circuit is closed, the magnetic field of the coil builds up and generates a self-induction voltage which counteracts the increase.  An incandescent lamp in the circuit lights up only gradually.

10- Discharge Curve of a Capacitor
A capacitor is charged by way of a resistor. The current is measured as a function of time and the effects of capacitance, resistance and the voltage applied are determined.