Reply
Sat 18 Nov, 2006 12:46 am
Subject: FLASHLIGHT
IF: [1.5v battery] connected to [BULB] - Gives you 1.5v worth of light, over the lifetime of the battery... let's say 10 hours just for example.
THEN, DOES:
[1.5v battery]+[1.5v battery] = 3.0v over 10 hours,
OR
[1.5v battery]+[1.5v battery] = 1.5v over 20 hours?
Are the batteries ( 2) connected to the same bulb (1) or is each battery connected to a separate and distinct bulb?
Is this one of those "series" v "parallel" questions?
No just one bulb. And I'm not up to the level of paralell/series questions yet.
Guess that'll be next.
Batteries would be like this: (if this text-art looks right)
--[BATTERY]--[BATTERY]--------(BULB)
|-------------------------------------|
I'll say that the life will be extended to 20 hours, since the voltage is constant, but life of power is doubled.
See This - a primer on the whys and hows of various battery connection configurations.
Quote:Figure 1: Serial connection
of four cells.
Adding cells in a string increases the voltage but the current remains the same.
1.5 +1.5 = 3 volts or 20 hours of light.
"Voltage", per se, is a red herring. What matters for harmonic's question is capacity to deliver current - do work - over time; amperage.
Any given battery will have a given capacity in amp hours of output at a given voltage, in the case of typical household batteries, milliamps, or thousandths of an amp. Typical household batteries, AAA, AA, C, and D types, for example, will be nominally in the range of 1.2 to 1.5 volts, however, the milliamp/hour output capacity of a D cell will be several times that of a much smaller AAA cell - same voltage, different capacity. Discharging into the same load, the larger battery will last longer. By connecting smaller batteries in parallel, the effect of a larger battery of the same voltage is achieved; the battery pack will last longer under the same load than will a single battery of the type comprising the batteries within the pack.
The student already said his class wasn't on series etc, yet.
Thats what he said, but that doesn't affect the fact what he's talking about the difference between series and parallel connection, whether that's what he said he wanted to talk about or not.
Adding the voltages - series connection - will cause a bulb to burn brighter, not longer. That's his example.
Adding the milliamp/hour capacity - parallel connection - will light the bulb longer without materially affecting its brightness. 2 totally different things going on there, and you're not gonna get what you want unless you know how to get it.
timberlandko wrote:Thats what he said, but that doesn't affect the fact what he's talking about the difference between series and parallel connection, whether that's what he said he wanted to talk about or not.
Adding the voltages - series connection - will cause a bulb to burn brighter, not longer. That's his example.
Adding the milliamp/hour capacity - parallel connection - will light the bulb longer without materially affecting its brightness. 2 totally different things going on there, and you're not gonna get what you want unless you know how to get it.
You're making a big deal out of nothing.
Oh, I'd say the distinction I made precisely is the answer to the question, whether or not that's the answer sought. What harmonic described is a series configuration, which will cause his bulb to burn brighter, not longer. Its not a "big deal", its THE deal. Not much point trying to do poetry if one can't do language.
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