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HELP!! Need answers for test!!!

  1. What is the optimum induced ac voltage on alarm circuits?a)2.0,b)1.0,c)0.5 or d)0.1 volts?

2.What is the unit of measure for attenuation for a cable?a)volts, b)decilels, c)Amps or d)Watts?

3.A detector installed in a residence that would meet U.L. requirements would be...a)Extent 1, b)Extent 2, c)Basic, or d)Perimeter?

4.During troubleshooting, the voltage should be checked...a)under max load, b)Normal operation, c)switches in test or d)switches open?

5.What type of branch circuit should be avoided for powering security systems...a)G.F.I., b)lighting, c)Gen Purpose or d)Laundry room?

6.To what height above the floor must wiring be protected...6,7,8 or 10 feet?

7.What is the minimum temp variance needed to trip a passive infrared motion detector...1,2,3 or 4 degrees?

8.In a 12 volt system, what voltage should be read across a closed switch with a 6k ohm resistor?

Reply to
Gator
Loading thread data ...

I hate tests...

  1. D? No clue
  2. B
  3. A
  4. A
  5. A
  6. 8
  7. 4
  8. .02 volts?

Reply to
Jim Rojas

Attenuation is measured in dB.

Bob

Reply to
Robertm

thanks for the help! A couple more...What is the maximum distance 18AWG wire is suitable for a self contained siren? What is the maximum allowable voltage drop for an audible device? What device reduces current?a)resistor, b)capacitor?

Reply to
Gator

Not enough information given for an (a) or (b) answer. A resistor will reduce both ac and dc current. A capacitor will reduce ac current dependent on frequency and value of capacitor, while completely blocking dc current. If we are talking dc, then a resistor will reduce the current somewhat whereas a capacitor will reduce it to zero after the initial inrush current.

Bob

Reply to
Robertm

cent Resistor

Jim Rojas

Reply to
Jim Rojas

ent Resistor

Jim Rojas

Reply to
Jim Rojas

If someone is asking these questions, they really need to study electronics instead of memorizing answers.

Bob

Reply to
Robertm

And db mean decibels...so B

"Robertm" a écrit dans le message de news: dnetof$8ph2$ snipped-for-privacy@news3.infoave.net...

Reply to
petem

those question look like they are coming from a wanabe electronic teacher..

there are mostly not enough info to provide real good answer..

"Robertm" a écrit dans le message de news: dneum7$8pri$ snipped-for-privacy@news3.infoave.net...

Reply to
petem

Hey, I'm an electrical engineer, not a typist.

Bob

Reply to
Robertm

It should have been the other way around, Db, not dB. I type with two finger and sometimes one finger gets there ahead of the other one. Yes, according to my engineering manual, the "D" is capitalized, it isn't db.

Bob

Reply to
Robertm

I did some further looking. We are both correct. From another book, "Decibels may be expressed as either Db or db, although the former is falling into disuse in favor of the latter." You must be younger than I am.

Bob

Reply to
Robertm

A resistor won't reduce current. It'll drop voltage, but the current remains unaffected. A capacitor will reduce current.

Reply to
Frank Olson

I agree, if we are looking strictly at the added resistor, it is a voltage dropping device, not a current dropping device, and all calculations for the load are based on the dropping voltage across the added resistor even though the net effect of the resistor is that the current will be reduced by reducing the voltage, assuming a series resistive circuit.

Bob

Reply to
Robertm

Also, has anyone considered that this is helping someone cheat on a test?

Reply to
Jim

Reply to
Bass' Helper

Hey I am French Canadian,trying to type English,how can I in any way try to be a typist either..

"Robertm" a écrit dans le message de news: dnf0vt$8qrp$ snipped-for-privacy@news3.infoave.net...

Reply to
petem

db Db dB what ever!

I was just pointing to the fellow that your answer was right and if he didn't knew about decibels and that they can be expressed by Db or db or what ever,the good answer was B

MAN!!!!

"Robertm" a écrit dans le message de news: dnf18d$8r1d$ snipped-for-privacy@news3.infoave.net...

Reply to
petem

I do not agree and this link will say the same

formatting link
a resistor is limiting current not voltage

"Robertm" a écrit dans le message de news: dnf3hr$8ru3$ snipped-for-privacy@news3.infoave.net...

Reply to
petem

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