Series and
Parallel
Circuits Examples
side by side
same in each component
Same across each component
Workbook
pages 88-89
Christmas fairy lights
Garfield graphics reproduced with kind permission from PAWS Inc. –All rights reserved –LOJ October 2007
House lighting
Garfield graphics reproduced with kind permission from PAWS Inc. –All rights reserved –LOJ October 2007
12V
Each bulb is designed to have a p.d. of 12V. They
therefore are connected in series and share the
voltage of 230V –getting about 12V each.
1A
If one bulb blows or comes loose all of the others go
out –if they were in parallel this would not happen
6V
4V
The ones designed to be in series have a small operating voltage they
would therefore blow if you put them in a socket designed for a parallel
lamp.
Garfield graphics reproduced with kind permission from PAWS Inc. –All rights reserved –LOJ October 2007
Garfield graphics reproduced with kind permission from PAWS Inc. –All rights reserved –LOJ October 2007
V = 12V; R= 2and V=IR so I = V/R = 12/2 = 6A
V = 12V; R= 4and V=IR so I = V/R = 12/4 = 3A
12V
12V
It allows 2A through it so it must be 3x the resistance
of the 2one –6
(OR R = V/I = 12/2 = 6A)
If the engine isn’
t running the battery is steadily drained of voltage.
If you had the lights on and then switched on the fan you would be
making the battery lose charge quickly –that would result in a lower
p.d. and the lights would go dim.
The Christmas tree lights are connected in series –if you break the
circuit by unscrewing a bulb no current will flow at all and all of the
bulbs will go out..
3A + 2A = 5A (remember the 6A current is not flowing!)
The wall lights are controlled by a single switch but are in par allel –
you can tell this because if one bulb blows the other stays on.
Garfield graphics reproduced with kind permission from PAWS Inc. –All rights reserved –LOJ October 2007
Garfield graphics reproduced with kind permission from PAWS Inc. –All rights reserved –LOJ October 2007