ELECTRICITY AND MAGNETISM LAB

fiftysixpowersΗλεκτρονική - Συσκευές

18 Οκτ 2013 (πριν από 3 χρόνια και 7 μήνες)

70 εμφανίσεις

ELECTRICITY AND MAGNETISM LAB

(These laboratory experiences are adapted from the
Conceptual Physical Science
Laboratory Manual
)




Introducti
on


Electricity and magnetism are the foundation of today's modern society. We rely on
electricity and magnetism to provide us with light, start our cars, and run our computer.
Today's laboratory is an exploratory lab to develop a qualitative feel for the
two basic
electrical circuits, series and parallel, and magnetism.


Science Information

For electrical current to flow in a wire or electrical device a potential difference
(measured in Volts) must be established between the two ends of the wire. One of t
he
simplest devices for establishing a potential difference is to use a battery. In many ways a
potential difference is like having a waterfall. The water will fall from a higher area to a
lower area. In the process the water can do work.


For example, a 1
.5V battery can provide 1.5 Joules of energy for each Coulomb of charge
that moves through the circuit. This energy can be used to light lights or ring buzzers.
The two slots in a wall socket have a potential difference of 120 V or 120 J per Coulomb
of cha
rge. This can be used to run computers or toasters.


The first part of this lab looks at how the current is distributed in an electrical circuit. In
the second part you will
examine distribution of energy in different (series and parallel)
bulb arrangement
s. For this purpose you will
use a hand cranked generator to produce the
potential difference to
power

the light

bulbs. The g
enerator
converts mechanical energy

(
Work done = F
orce x
D
istance)

into electrical energy

as you turn a coil of wire in the
presenc
e of a magnetic field.


Closely related to the study of electricity is the study of magnetism. In the third part of
the lab you will observe the different configurations of a magnetic field. The magnetic
field itself is result of the motio
ns of electrons a
round the
atoms

of (so called
ferromagnetic) elements like iron.

Moving electrical charges produce magnetic fields.


Part I: Batteries and Bulbs


Discussion


Many devices include electronic circuitry, most of which are quite complicated. Complex
circuits
are made, however, from simple circuits. In this activity we build one of the
simplest yet most useful circuits ever invented for lighting a light bulb! To the right are
common elements found in electric circuits. It is common to call a single cell a batte
ry,
but strictly speaking, a battery refers to a combination of cells. So instead of saying "a
battery of cells," we simply say "a battery."


Follow procedures
related to part I

in the answer template. Answer associated questions.



Part II: Cranking Up


Purpose

To compare qualitatively the power inputs to a series and to a parallel circuit.


Discussion

Here's a chance to both see and feel some differences between series and parallel circuits.


Follow procedures related to part II in the answer template. A
nswer associated questions.




Part III: Magnetic Personality


Purpose


To explore the influence of a moving magnet in a coil of wire
--
electromagnetic induction.


Follow procedures related to part III in the answer template. Answer associated
questions.



Part IV:

Explain how are parts II and III related




Key Terms: electrons, electric current, voltage, resistance, electric circuit, parallel circuit,
serious circuit, magnets, magnetism, electric power,
voltage
source, battery, conductor,
resistor, bul
b, electric generator, induced current
, Ampere, Volt, Ohm
.