### PEN156 Electricity and Magnetism Laboratory

The objective of this course is to teach electricity and magnetism by observations from experiments. This approach complements the classroom experience of PHY102 Physics II, where the material is learnt from lectures and books designed to teach and improve the problem solving skills of students.

The laboratory begins with the introduction to the electricity  magnetism laboratory, where the use of avometer to measure the current, voltage and resistance is taught. Also, the students learn to read the resistance of unknown resistors from color codes.

Ohm's law and the equivalent resistance concepts are taught and practiced for serial as well as parallel connection of resistors.

Students examine the electric fields and equipotential surfaces generated by  the charge distributions in parallel plates and circular electrodes.

Permittivity of free space is experimentally calculated by measuring the voltage and accumulated charge across an empty parallel-plate capacitor. The permittivity of free space is also calculated for a fixed applied voltage by changing the distance between the plates of the parallel plate capacitor. Moreover, the relative permittivity of a plastic and a glass layer is measured by using the parallel plate capacitor.

Kirchoff's laws are proved through a circuit that consists of two-loops with a voltage source in each loop.

Capacitors are introduced as charge-storing circuit elements. The speed of charge and discharge of a capacitor in an RC circuit is examined.

An introduction to non-Ohmic devices is given. The current-voltage characteristics of tungsten filament (bulb) is investigated.

Current-voltage characteristics of a semiconductor diode is investigated for forward and reverse bias.

An introduction to alternating current (AC) and voltage is done. The amplitude, period and frequency of a wave in AC form are read from an oscillope screen connected to a signal generator.

half-wave rectifier is established with a diode and a resistor and the students learn how to convert AC power to DC power.

An introduction to magnetic fields is given. Magnetic field distribution of a coil is examined as a function of the length and number of turns of the coil, and the permeability of free space is found experimentally.

Thr spatial distribution of magnetic field is investigated between a pair of coils in the Helmholtz arrangement for different separation distances and different current-flowing directions.

Faraday's law of electromagnetic induction is examined which is the basis of induction motors. The voltage induced across thin coils which are pushed into the long coil are determined as a function of frequency, number of turns, diameter and magnetic field strength.

A compensation of one experiment is done for the students who miss one experiment.