Circuit Construction Kit (DC Only) Simulation

winetediousElectronics - Devices

Oct 7, 2013 (4 years and 1 month ago)

143 views

Electricity Web Simulations
Day 2

Page
1

of
4

Name









Date




Class




C
ircuit Construction Kit (DC Only) Simulation

In this simulation you will build circuits with resistors, light bulbs, batteries, and switches. Take measurements with the
ammeter and voltmeter. View the circuit as a schematic

diagram, or switch to a life
-
like view.

Directions:



Click on circuit construction kit (DC only)



Click on Run Now.

Series Circuits

1.

Simple
Series

Circuit
-

One Resistor

a)

Construct a simple circuit that contains the following components: Light bulb,

wire and

a

10
-
V ba
ttery.

Do not
use a resistor
.
See diagram to make sure
you have done this correctly.
Pay careful
attention to the light bulb. Notice that there
are two small dotted circles on the light
bulb base. Each wire must connect to a
different circle
.

b)

C
heck off non
-
contact
ammeter

and
voltmeter under tools on the right side
.

i)

Make sure that the components are in
series so you can trace a charge
traveling through the entire circuit from
the positive end of the battery to the negative end.

ii)

Right
-
click the

battery. Check the “Show Value” box

it should read 10 V
.

If not correct

iii)

Right
-
click the
light bulb
. Check the “Show Value” box

it should read 10 Ω. If not correct.

c)

Use the voltmeter to confirm that the voltage of the battery is in fact 10 volts.

Do this

by placing the
red probe
on the battery where the electrons enter and the black probe on the side where the electrons exit the battery.

If
it is not 10 volts, change it by right
-
clicking the battery and
using the keyboard

to enter in 10V.

d)

Record the curr
ent flowing through the circuit by read
ing the ammeter value:



e)

Use Ohm’s Law to predict the resistance of the light
bulb. Show work in space provided
:

R
bulb

=





Electricity Web Simulations
Day 2

Page
2

of
4

f)

Confirm this resistance by right clicking on the light bulb and then clicking the “Change

Resistance” button. You
should see the resistance listed on the screen.

g)

Was Ohm’s Law verified here?


Why or why not?








2.

Simple
Series

Circuit
-

Two Resistors

a)

Add another light bulb in series to the simple circuit above.
To do this
right click on one
of

the gr
ay circle
s

where a wire connects and select split junction
. Then add

additional light

bulbs and wire as needed.

b)

Right click both
light bulb
s to make sure they are

10
-
Ω light bulb
s
.

c)

Confirm that
the battery is still 10
-
volt

using the voltmeter.

d)

Determine the current flowing through the circuit
by
hovering the non
-
contact ammeter over the wire. Record

the
ammeter reading here:




e)

In a series circuit the total resista
nce is sum of the resistance of ALL the
light bulbs
. Based on that fact
determine the total resistance of the 2
light bulb

circuit.
R
total
=




f)

Add a third light bulb to the circuit by connecting it in series to the o
thers. Repeat steps b through e

and
c
alculate the
total resistance

of the 3 bulbs. Record this resistance here: R
total

=




g)

W
hat is the formula for equivalent resistance in a series
circuit?





















Now stop using the computer and solve the following 4 questions. Show all work

in the space below the
question.

1.

U
sing Ohm’s Law, calculate the current
I

flowing through
the cir
cuit in diagram to the right.

Show work in the
space provided.

I =






2.

What is R
eq

for th
e circuit in Figure to the
left
?



3.

Using Ohm’s Law and your value
for R
total

calculate the current
I

flowing through the circuit.

Show work in the space provided.


I =






Electricity Web Simulations
Day 2

Page
3

of
4

4.

How could a resistor be used to prevent

a 4
-
Ω car speaker from blowing out due to too much current?































Parallel Circuits
vs.

Series Circuits

1.

Build a Series Circuit

a)

Build a circuit with one 10 ohm (Ω)
light bulb

and a 10 volt battery.

b)

Place an ammeter where the current

leaves the battery.

i)

Record the value here: ________

c)

Now put a second
light bulb

in series

with the first light bulb.

i)

Record the new current here: ________

d)

Using what you learned in the previous simulation about total resistance, determine the total resi
stance for this
circuit. Record the total resistance of the circuit here: _______

e)

Note how bright each
light bulb

is when in

series by developing your own
brightness scale. Rank the
brightness of your bulbs on a 1
-
10 scale. Record the ranking here: ____
____

Clear your screen.


2.

Build a parallel circuit

a)

Now build a parallel circuit with a 10 volt battery and
two

10 ohm
light bulbs
.

b)

See the d
iagram
to the right
for how to set this up.


c)

Record the brightness of the
light bulbs

using the same
brightness scal
e as before.



d)

Place an ammeter where the current leaves the battery.

i)

R
ecord the value here:



e)

Place an ammeter in each branch next to the
light bulb
.

i)

Record
the first value here:




ii)

Record the second value

here:



f)

What do you notice about the current

in each branch compared to the current leaving the battery?
















g)

What do you notice about the total current as it leaves the battery in series as compared to when it leaves the
battery in parallel? Is this a good or a bad thing?






















Electricity Web Simulations
Day 2

Page
4

of
4

Comparing t
he 2 types of

Circuits

h)

Were the
light bulbs

brighter when wired in series or parallel?







i)

I
s the
current leaving the battery bigger when the bulbs are wired in series or in parallel
?




j)

If the curr
ent is bigger, according to O
hm’
s law the resistance is smaller.
Is the resistance bigger in a series or
parallel circuit?







3.

Parallel Circuits Further Investigations

a)

Now change the resistance of one of the
light bulbs

to 20 ohms.

i)

Record the total current le
aving the battery here:



ii)

Record the current in

the 20 ohm branch here:



iii)

Record the current in

the 10 ohm branch here:



b)

Which
light bulb

got more current?




Why?





















c)

What do you notice about the current in each branch compared to the current leaving the batte
ry?
















d)

Wh
ich
light bulb

is brighter?



Why?