heat through wires?

[pitzel_001]

hi. i'm looking for info for my science fair project (i'm in grade 8.) i know that heat can easily travel through wires. does this require many materials/large materials? (I'm building a heated snow shovel, and am trying to find a way to heat the handle enough to keep hands comfortable at the -40 degree temperatures we encounter where i live. i hope that heating the handle would not be complicated and could be done with small materials like light gauge wire and maybe AA batteries or something) obviously, i know very little about this, any help would be appreciated!

thank you,

[Glider]

You can buy heated handlebar grips for motorcycles. You might like to look at how they are constructed. They run off the bike's battery (12v).

[coquina]

hi. i'm looking for info for my science fair project (i'm in grade 8.) i know that heat can easily travel through wires. does this require many materials/large materials? (I'm building a heated snow shovel' date=' and am trying to find a way to heat the handle enough to keep hands comfortable at the -40 degree temperatures we encounter where i live. i hope that heating the handle would not be complicated and could be done with small materials like light gauge wire and maybe AA batteries or something) obviously, i know very little about this, any help would be appreciated!

thank you, [/quote']

 

Resistance heat, like that which runs through wires (like a toaster or an iron) use a lot of electricity, and batteries are heavy. Maybe you could make the handle a hollow aluminum tube and fill it with "C" or "D" batteries, or maybe you could use the kind of batteries that are rechargable, like the ones that come in craftsman products and have recharging stands.

[Edward]

Well it is an interesting idea but I think you need to worry more about how to distribut the heat safely. You don't want the handle to over heat and burn the skin on your hand. How do you plan on heating the knuckles of the hand? what is the avantage of this over wearing gloves or mittenes with or without chemical heating pads inside? You may want to consider using chemical heating instead of electric. Where abouts do you with temperatures like that?

[Lance]

Try filling the handle with plaster of paris and nichrome wire then have a battery pack in your pocket.

[5614]

an electrical heater requires, relative to other electrical components, a vast amount of power... you want to look at other ways of getting the heat from electricty... the heating effect of wires is most commonly seen in haid dryers... look in one and you see the fan and coils, thats wire, electricity goes down the wire, heats it up and fan blows it out.

[swansont]

an electrical heater requires, relative to other electrical components, a vast amount of power... you want to look at other ways of getting the heat from electricty... the heating effect of wires is most commonly seen in haid dryers... look in one and you see the fan and coils, thats wire, electricity goes down the wire, heats it up and fan blows it out.

 

And a lot of hair dryers are rated in the vicinity of a kiloWatt. That'll drain your battery right quick.

[5614]

2 simple relevant equations are:

 

power (watts) = current (amps) x voltage (volts)

 

and

 

voltage (volts) = current (amps) x resistance

 

and you can of course rearrange those.

 

does energy loss = current(sqaured) x resistance or (i^2)r.... or is that something else?

[Lance]

And a lot of hair dryers are rated in the vicinity of a kiloWatt. That'll drain your battery right quick.

 

Heating air is a lot less efficiant than heating a handle. If that same amount of power was used in a shovel the handle would melt.

 

Nichrome wire is whats used used in hair dryers. Of course there is no way you are going to get the entire assemply including the batteries inside the handle.

[5614]

Of course there is no way you are going to get the entire assemply including the batteries inside the handle.

why not? all he needs is the battery and wire. obviously the wire fits in, well those small disc batteries can be connect in series, whilst they are expensive its possible.

[Lance]

why not? all he needs is the battery and wire. obviously the wire fits in, well those small disc batteries can be connect in series, whilst they are expensive its possible.

 

But if you used those small batteries they can supply the required current but they will run out within minutes. Im assuming he wants it to be heated for around an hour or longer. Also, you dont want the resisistive elements to heat the batteries.

[5614]

true, but at the same time you dont want to have to plug your snow shovel into the plug to make it work!

 

"can you come and help me dig my car outta the snow"

 

"no, sorry, my spade needs to be plugged in to work"

 

looking back to the original post, AA batteries would work yes, but as Lance pointed out in a circuit such as this, remember that current = voltage/resistance and there is very little resistance in just some wire, so the current draw will be high, this will drain the batteries quite quickly... i suggest you try different amounts of batteries for values of how long they will last.

[pitzel_001]

Thanks for the help, guys. i think i've got some ideas.

ps. if you steal my idea i will hurt you with mean words.

[coquina]

As far as batteries go - I think the rechargable kind that are used in power tools would work best. They usually take 2 batteries, which could fit in the bottom part of the handle below the "Y". While you are using two you are charging the other two in their charger.

 

If you keep the shovel inside, where it is warm, the handle will be warm when you take it out and the warmth of your gloved hands should keep it that way. That is, unless you lay the thing down in the snow while you make snow angels or have a snowball fight.

 

A cheaper option would be to wrap the metal handle with a short length of hose insulation and duct tape it in place.

[Edward]

Are you gonna answer my question?

[YT2095]

hi. i'm looking for info for my science fair project (i'm in grade 8.) i know that heat can easily travel through wires. does this require many materials/large materials? (I'm building a heated snow shovel' date=' and am trying to find a way to heat the handle enough to keep hands comfortable at the -40 degree temperatures we encounter where i live. i hope that heating the handle would not be complicated and could be done with small materials like light gauge wire and maybe AA batteries or something) obviously, i know very little about this, any help would be appreciated!

thank you, [/quote']

 

don`t bother with electricity then.

a supper saturated soln of sodium acetate in a PVC screw off handle with a spring trigger activator, will give a few hours of nice comfortable heat without the bulk and weight.

all you`ll need to do is screw the handle off, place it in a pan of boiling water for 10 mins, and it`s charged and ready to go for the next cold session

 

 

that`s the way I`de go

[pitzel_001]

edward -- i live in canada, where it gets so cold in winter that exposed skin freezes in about 2 minutes. thats why you need facemasks, gloves, 4 layers of sweaters, etc. although, in summer it gets up to 25 degrees celsius on any given day.

 

by the way, YT2095, what's a soln? is that supposed to say solution?

[5614]

yes he meant a super saturated solution

[pitzel_001]

ohhhhhh i get it. thanks for the clarification