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which Battery life drain faster

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karthikkrv85

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Hai friends

I wanted to know a detail about battery life.

Consider 2 network as follows

1. A battery (12V) is closed with a resister(200 ohms) and a bulb (10W)

2. A battery (12V) is closed with a resister(2000 ohms) and a bulb (10W)

From the above 2 circuits, which battery life will drain faster and how

(My guess is 2nd network)

Thanks and regards,
karthikkr
 

You didnt say serial or parallel connection of resistor and bulb ? I consider serial conection.

Battery with 200R will drain faster.
 

(again suspecting series connection)

Well, if the bulb is a filament bulb, then it's resistance is 12²/10 = 14.4Ω at running temperature. It is not going to get anywhere that temperature with those big resistances in series though, so its resistance will be a fair bit lower than that.

The bulbs resistance then is not of much significance compared to the 200Ω resistor, and even less (and it's colder so lower resistance again) compared to the 2000Ω resistor.

So, let's assume just the resistors:

12V/200Ω = 0.06 amperes
12V/2000Ω = 0.006 amperes

So, the 200Ω resistor circuit will drain the battery about ten times faster than the 2000Ω resistor circuit due to drawing ten times the current.

That does depend a little on the size of the battery, but let's assume that it's big enough that the difference in discharge rate is insignificant.
 
tpetar said:
Resistor of 2000R is higher resistance then 200R and in circuit you have smaller current then in 200R circuit.

If you drain more current from bat, bat will be empty faster.




Basics :

http://www.sengpielaudio.com/calculator-ohmslaw.htm

http://www.the12volt.com/ohm/ohmslawcalculators.asp
Click to expand...

Hai thanks for your explanation.

A higher valued resistor blocks high current. Does that mean it is not going to consume the current or it is going to dissipate the current interms of heat?
 

You need to use Ohm's law. V = I * R

Both resistors will dissipate energy as heat, but that's not really significant in your example.
 

I have one question for You karthikkrv85, but I please you that you dont try this!!!!!


What You think what will happen when connect copper wire on battery ? (short circuit with wire)
Will copper explode, heat and fire ? Or what ? And why ?


You can try this on 1,5V small battery AAA or AA! Use thin wire. NOT with Car battery!!!!!


Wire will be very hot, with some smoke. Wire have small resistance high current will flow! In circuit you have small resistance and high current go.

If you add resistor 200R on AA or AAA battery what will happen?
You can test this with unimer - ampermeter to see current.
 
Last edited:
Let's look at it from basics:

The battery, by way of a chemical reaction, provides an electromotive force (EMF) because of the potential difference (PD, measured in volts) between its terminals.

Electrons in the wires, bulb and resistor are moved due to this force (because they are charged particles). The quantity of this movement is called current.

The lower a resistance something has, the more easily the electrons in it can move, and so the current will be higher (for the same PD).

The battery only has a certain capacity of energy (which is being used to drive the current through the conductors, and is dissipated in them) and so will run out. the more current (thus more energy) involved, the quicker the battery runs out.

Does that help?
 
Yes i understand this. I was considering that when we block high current flow with higher resister, the resister dissipates the more amount of current as heat.

But actually, when we try to limit high current flow with small resister, the amount of heat will be larger than the higher valued resister.

Thanks guys.

Basic confusion
 


karthikkrv85 said:
Hai friends

I wanted to know a detail about battery life.

Consider 2 network as follows

1. A battery (12V) is closed with a resister(200 ohms) and a bulb (10W)

2. A battery (12V) is closed with a resister(2000 ohms) and a bulb (10W)

From the above 2 circuits, which battery life will drain faster and how

(My guess is 2nd network)

Thanks and regards,
karthikkr
Click to expand...

Series or parallel, combination 1 will draw higher current and drain the battery faster. After having read the previous posts, you should be able to explain why.
 

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