Electricity and Magnetism

Preface
- Getting Started
  
  These labs have been developed with a view to providing the students with meaningful and significant experience with experimental processes...
- Role of WebAssign
  
  Your physics department decides whether to use WebAssign for labs...
- Lab Syllabus
  
  Lab assignments are common for all students taking the lab...
- Working In Groups
  
  In your labs, you will be working in cooperative groups...
- Tips From Students
  
  These tips are based on written comments from 275 former physics lab students who used WebAssign for their lab assignments...
Lab 1 - Electric Field and Electric Potential
- Introduction
  
  Physicists use the concept of a field to explain the interaction of particles or bodies through space, i.e., the "action-at-a-distance" force between two bodies that are not in physical contact...
- Discussion of Principles
  
  A charged body experiences a force whenever it is placed in an electric field. The vector relationship between the force and the electric field is given by...
- Objective
  
  The objective of this experiment is to draw equipotential lines for four different charge configurations. You will then use these equipotential lines to map the electric field lines for each configuration.
- Equipment
  
  PASCO scientific field mapper, Capstone software, Power supply, Electrodes, Voltage probe
- Procedure
  
  You will use the PASCO scientific field mapper, which consists of a sheet of carbon-impregnated paper. The electrodes or charged bodies are formed by a line of conductive ink, which has been drawn on the paper and then allowed to dry...
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
Lab 2 - Capacitors
- Introduction
  
  The basic function of a capacitor is to store charge and thereby electrical energy. That energy can be retrieved at a later time for a variety of uses...
- Discussion of Principles
  
  A capacitor is a set of two metal conductors separated by a small distance. Usually some type of dielectric (non-conducting) material is placed between the two conductors....
- Objective
  
  The objective of this experiment is to study the characteristics of capacitors in series and parallel arrangements and to qualitatively investigate the energy stored in such arrangements.
- Equipment
  
  Signal interface with power output, Capstone software, multimeter, capacitance meter...
- Procedure
  
  This lab consists of four parts. The first procedure is a qualitative investigation of the energy stored by different arrangements of capacitors...
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
- Appendix for Lab 2
  
  Here is a list of all of the appendicies referenced in this lab.
Lab 3 - DC Circuits and Ohm's Law
- Introduction
  
  During the nineteenth century so many advances were made in understanding the electrical nature of matter that it has been called the "age of electricity." One such advance was made by a German physicist named Georg Simon Ohm...
- Discussion of Principles
  
  Ohm's Law can be written algebraically as ΔV = RI, where ΔV, measured in volts, represents the potential drop or potential difference across the conductor, I is the current in the conductor measured in amperes...
- Objective
  
  The objective of this experiment is to use Ohm's Law to determine the resistance of several individual resistors and the equivalent resistance of series and parallel combinations. You will apply various voltages across...
- Equipment
  
  PASCO circuit board with two unknown resistors, DC power supply—adjustable from 0 to 5 V, Two hand-held multimeters, Connecting wires
- Procedure
  
  You will set up a simple DC circuit with a single resistor and measure the current flowing through the resistor and the potential difference across it...
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
- Appendix for Lab 3
  
  Here is a list of all of the appendicies referenced in this lab.
Lab 4 - Charge and Discharge of a Capacitor
- Introduction
  
  Capacitors are devices that can store electric charge and energy. Capacitors have several uses, such as filters in DC power supplies and as energy storage banks for pulsed lasers...
- Discussion of Principles
  
  A capacitor consists of two conductors separated by a small distance. When the conductors are connected to a charging device (for example, a battery)...
- Objective
  
  In this experiment a (computer-emulated) oscilloscope will be used to monitor the potential difference, and thus, indirectly, the charge on a capacitor...
- Equipment
  
  PASCO circuit board, Signal interface with power output, connecting wires, Capstone software
- Procedure
  
  The RLC circuit board that you will be using consists of three resistors and two capacitors among other elements. See Fig. 6 below. In theory you can, therefore, have different combinations of resistors and capacitors...
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
- Appendix for Lab 4
  
  Here is a list of all of the appendicies referenced in this lab.
Lab 5 - Force on a Wire
- Introduction
  
  A stationary or moving electric charge will experience a force when placed in an electric field. On the other hand, an electric charge has to be moving to experience a force due to a magnetic field...
- Discussion of Principles
  
  The magnitude of the force exerted by a magnetic field on a short, straight wire of length L that carries a current I is given by the equation...
- Objective
  
  The objective of this experiment is to determine the magnitude of the magnetic field by measuring the force experienced by a current-carrying wire placed in this magnetic field.
- Equipment
  
  Magnet assembly, Digital balance, Rectangular loop of wire of multiple turns, Ring stand, Signal interface with power output...
- Procedure
  
  The wire loop has different number of turns This allows you to change the length of the wire through which the current flows...
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
- Appendix for Lab 5
  
  Here is a list of all of the appendicies referenced in this lab.
Lab 6 - Optics
- Introduction
  
  Geometric optics is one of the oldest branches of physics, dealing with the laws of reflection and refraction. Reflection takes place on the surface of an object, and refraction occurs when light passes through an object...
- Discussion of Principles
  
  When light is incident on a surface, some of the light is reflected back while some of it is transmitted or absorbed. A plane mirror is a highly polished surface with minimal absorption or refraction of light. Nearly all of the light is reflected back...
- Objective
  
  The objective of this experiment is to study the path of light rays due to reflection and refraction at plane and curved surfaces and to verify the Law of Reflection in a plane mirror and Snell's Law of refraction.
- Equipment
  
  Acrylic block, Light ray box, Plane mirror, Converging and diverging lenses, Converging mirror, Sheets of paper, Ruler, Protractor
- Procedure
  
  You will use a light ray box to produce parallel rays of light into which you will insert various optical components to observe their effect on the rays. You will trace the rays on sheets of white paper, which will constitute part of your data for this experiment.
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
- Appendix for Lab 6
  
  Here is a list of all of the appendicies referenced in this lab.
Lab 7 - LR Circuits
- Introduction
  
  The English physicist Michael Faraday found in 1831 that when the current through a coil changes, the coil produces a changing magnetic field (in addition to the field of the changing current), which induces an electromotive force ("emf") in the coil itself...
- Discussion of Principles
  
  The inductance of a circuit, usually symbolized by L, and measured in henry (H), is the tendency of a circuit to oppose any changes in the current. This opposition to a change in the current shows up as a slowing of the rise or fall of the current in circuits...
- Objective
  
  The objective of this experiment is to examine the dynamic behavior of an LR circuit by using an oscilloscope to visualize the voltage across the resistor for both rising and decreasing current...
- Equipment
  
  PASCO circuit board, Capstone software, Signal interface with power output, Connecting wires, Multimeter
- Procedure
  
  The RLC circuit board that you will be using consists of three resistors and one inductance coil among other elements. The value of the inductor can be changed by inserting an iron core into the coil...
- Worksheet
  
  You will use a hard copy of this worksheet to enter data as you work through the experiment in lab. Print the worksheet and bring it with you to the lab.
- Appendix for Lab 7
  
  Here is a list of all of the appendicies referenced in this lab.

Appendix