Electrical question: 12 Volt Battery charger: How many joules does it have

[Clarence Martinn]

Anyone know how many Joules or volts a regular 12 Volt car battery charger produces ? Saw plans for making an electric Rat trap, and they hooked a car battery charger up to it . Would that really work ?

[Roger Nair]

Clarence, your information is incomplete. A joule is a measurement of work. A volt is electrical potential or electromotive force. A watt is power equal to volts times amps. An equivalence exists between joules and watts. So you will need to know the amps to calculate the watts of your battery charger in order to know the power potential of the charger. Power input potential does not equal work output, it's the law.

[Clarence Martinn]

2 Amp slow charge

10 Amp regular charge and 50 Amp fast charge

[Pat Barry]

It outputs a little more than 12 vdc. Not enough to kill a rat unless there is something to jack up the voltage.

[Matt Schrum]

It outputs a little more than 12 vdc. Not enough to kill a rat unless there is something to jack up the voltage.

Agreed. Maybe they bought an electric fence charger that runs off of 12V and used the car charger to power that? Even then, you'll probably scare a rat before you kill it. I have a smaller fence charger, and while it is a couple of thousand volts, it is only 0.10J. It makes you regret touching it, but not a whole lot. At work I deal with some stuff that puts out upwards of 7J at 2kV. Now that'd give a rat a run for its money.

[Frank Pratt]

A joule is a measurement of work. A volt is electrical potential or electromotive force. A watt is power equal to volts times amps. An equivalence exists between joules and watts.

Almost, but not quite. there is an equivalency between a joule and a watt/hour. A watt is a rate o energy use, watt/hour or joule are measurements of a quantity of energy.

[Roger Nair]

Almost, but not quite. there is an equivalency between a joule and a watt/hour

Almost, but not quite. One joule equals one watt per second or one joule equals 1/3600 watts per hour. In SI units joule, watt and amp are all referenced to a second.

[Frank Pratt]

Almost, but not quite. One joule equals one watt per second or one joule equals 1/3600 watts per hour. In SI units joule, watt and amp are all referenced to a second.

These discussions can get complicated , and I don't always express myself very well. What I'm saying is that a joule and watt/hour are a quantity of energy, like a liter of water is a quantity of water. A watt is a rate of energy use, like how fast the water is flowing out of the hose.

[Kev Williams]

would those plans include a 12v ignition coil? Any 12v source and a coil can get you 40,000-ish volts. A quick shock won't kill humans, but it might take out a mouse...

[Bill Dufour]

My sister bought an electric rat trap and it worked well for her. They make them that will send a text when they trigger off.
Bill D.