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Mind bender #67665
07/11/06 09:44 PM
07/11/06 09:44 PM
B
Bill39  Offline OP
Member
Joined: Nov 2001
Posts: 75
Indianapolis, IN, USA
Here's one my son brought home from school and so far he's got me stumped:

Create a circuit in which initially, four lamps are ON while the fifth lamp is OFF. Also, you must be able to unscrew one of the four burning lamps in order to turn on the fifth lamp. You are not allowed to change any of the wiring to get this to work.

Darn College-boy!!

Work Gear for Electricians and the Trades
Re: Mind bender #67666
07/11/06 10:24 PM
07/11/06 10:24 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,166
Estero,Fl,usa
What kind of parts can I use?


Greg Fretwell
Re: Mind bender #67667
07/11/06 10:29 PM
07/11/06 10:29 PM
B
Bill39  Offline OP
Member
Joined: Nov 2001
Posts: 75
Indianapolis, IN, USA
A battery, the lamps, (& holders) & any # of wires you need.

That's it, no switches, etc. A simple circuit connected in any combination of series or parallel.

Re: Mind bender #67668
07/11/06 10:31 PM
07/11/06 10:31 PM
E
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Thyristor, zenor diode and SCR to control a relay? Multiples of each could do it arranged correctly, oh a few resistors too. Also what is the voltage and current?

You posted while I was pondering...

[This message has been edited by e57 (edited 07-11-2006).]


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Mind bender #67669
07/11/06 10:32 PM
07/11/06 10:32 PM
E
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Hmmm, not legal to install? But operational?

[This message has been edited by e57 (edited 07-11-2006).]


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Mind bender #67670
07/11/06 10:37 PM
07/11/06 10:37 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,166
Estero,Fl,usa
Are all of the light bulbs the same wattage?
If the 5th one was a small fraction of the others and in parallel with the one you unscrew it would work.
It sounds like one of those "all american five" radio filiment deals.


Greg Fretwell
Re: Mind bender #67671
07/11/06 10:39 PM
07/11/06 10:39 PM
E
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Voltage and lamp wattage?

You guys got me again in the two minute delay of my slow typing...

[This message has been edited by e57 (edited 07-11-2006).]


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Mind bender #67672
07/11/06 10:42 PM
07/11/06 10:42 PM
E
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Thats what I was thinking too.


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: Mind bender #67673
07/11/06 10:46 PM
07/11/06 10:46 PM
B
Bill39  Offline OP
Member
Joined: Nov 2001
Posts: 75
Indianapolis, IN, USA
Guys,
This is a college physics lab question.
No NEC code or inspectors to worry about.

Wattage of lamps was not given. The info in my original post is all the info the prof gave them.

Re: Mind bender #67674
07/11/06 11:16 PM
07/11/06 11:16 PM
L
LarryC  Offline
Member
Joined: Jul 2004
Posts: 783
Winchester, NH, US
Hint: Brooklyn

LarryC

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