Fundamentals of Circuits I: Current Models, Batteries & Bulbs

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Date:
Lab Partners:
Fundamentals of Circuits I:
Current Models, Batteries & Bulbs
Objectives
• To understand the nature of electric currents and why the current is the same at all points
in simple circuits.
• To understand that an electric potential difference (voltage) can cause a flow of electric
charge in a conductor.
• To gain practice in designing and building simple circuits with batteries, light bulbs and
switches.
• To learn to draw circuit diagrams using electrical symbols.
• To learn to make measurements of current ant voltage using microcomputer-based probes
Overview
In the labs during the first part of this semester you are going to do a series of activities
designed to help you develop a strong conceptual understanding of the nature of electric current
and electric potential difference (commonly referred to as Voltage), and the essential features
of simple electric circuits. These labs have been adapted from the Real Time Physics Active
Learning Laboratories [1]. The goals, guiding principles and procedures of these labs closely
parallel the implementations found in the work of those authors [1, 2, 3]. The ideas that you
will learn in these labs are the same ones that go into making all the electrical devices that play
an important role in our modern world-everything from electric lights and motors to TV sets,
computers and photocopy machines.
In several of these labs the electrical components we will work with are batteries and light
bulbs. A battery is a device that uses chemical energy to do work on the electric charges that
flow in it. As it does work it increases the electrical potential energy of these charges, which
generates an electric potential difference.
The energy added to the electric charge by the battery can be used to operate an electrical
device. In today’s experiment that device will be a light bulb. But in order to deliver the
energy to the light bulb the electric charge must flow through the battery and light bulb. This
requires the light bulb and battery to be connected using conductors, materials that allow
electric charges to flow in them.
In this lab you will consider several models that might explain the flow of charge and
predict the measurements that would result if the model is correct. You will then make the
measurements to determine which of the models correctly describes the flow of charge, and
which models do not.
PHYS-204: Physics II Laboratory 1