genuine question

[m1ck_b87]

Hi all I know a lot of people on this forum won't know this so I'm going to bring it up, potential difference.

Potential difference is voltage, so if I measure between live and a metal object will I get 230v. It is a difference in potential at the end of the day.

 

[Tridentsystems]

And your question is ?

 

[m1ck_b87]

My question is if I measure between live and any conductive object will I get 230v

 

[Baker1988]

aslong as the piece of metal is connected to earth in some way yes you should

 

[micknew]

Thats like asking if you would get a voltage between the positive and negative of 2 different batteries, what do you think?

 

[m1ck_b87]

Thats like asking if you would get a voltage between the positive and negative of 2 different batteries, what do you think?

So the object has got to connect to earth.

 

[m1ck_b87]

Why does it have to be connected to earth surely there's potential in anything conductive

 

[Tridentsystems]

Is this for real ? It's year 4 science With all due respect

 

[ayjay]

depends on the resistance of the earth
the neutral would be the best thing
are you a young lad?

 

[trev]

Why does it have to be connected to earth surely there's potential in anything conductive

If that's the case why don't birds get fried when they sit on power lines, There has to be a path to earth.

 

[Sintra]

Yes the circuit needs to be completed.

 

[micknew]

The potential is created by the generator or battery etc., conductors only have potential when connected to the power source.

 

[Tridentsystems]

Anything conductive has a potential to conduct, different to potential difference however

 

[m1ck_b87]

Why does it have to be connected to earth surely there's potential in anything conductive

If that's the case why don't birds get fried when they sit on power lines, There has to be a path to earth.

Why doesn't the electrical current pass through 1 birds leg and out the other and fry the bird

 

[Tridentsystems]

Have a google of current flow theory etc on some science sites. May help your understanding if you begin with simple battery circuits etc and even look at the analogies of water flow to visualise it

 

[Tridentsystems]

Minimal potential difference between feet. Electricity likes the path of least resistance. Offer the bird a nearby ground potential and you get a fried snack as the current wants to get to earth and the bird becomes the conductor

 

[trev]

Why doesn't the electrical current pass through 1 birds leg and out the other and fry the bird

Now I know you're having a laugh pal.

 

[micknew]

Why doesn't the electrical current pass through 1 birds leg and out the other and fry the bird

Because the potential difference between the birds feet is minute as the birds legs are close together.

 

[telectrix]

Why doesn't the electrical current pass through 1 birds leg and out the other and fry the bird

in actual fact, some current will flow through the bird's legs, as the bird is a parallel resistance to the wire it's standing on. however, the resistance of the bird's body is far greater than that of the cable between it's feet and so the current flow through the bird is negligible.

google resistors in parallel.

 

[micknew]

Now I know you're having a laugh pal.

And of course Trev your right, a plumber taking the P.

 

[micknew]

And of course Trev your right, a plumber taking the P.

Still, made me smile after a hard day!

 

[trev]

Having thought about your question a little more I think the easiest explanation regarding the bird on the wire is that the electrickery is flowing up each leg at the same time and meeting in the middle, both currents being equal, one is not stronger than the other so they just kind of stand there butting heads and getting no advantage, were you to fly up and touch the bird with one hand only you'd die because the electrickery is only entering your body through one point and doesn't meet the opposing current coming the other way. Grab it with both hands and you'd be ok though.

I am of course taking the p.

 

[telectrix]

on a similar note, andre previn should not sit on the wire because he's a good conductor.

 

[micknew]

on a similar note, andre previn should not sit on the wire because he's a good conductor.

Now your getting into advanced theory LOL.

 

[m1ck_b87]

Genuine question results in spasticated answers, thanks for the people that have positive answers so basically it has to be part of the electrical system

 

[trev]

The conductive part you're touching has to be connected to earth for current to flow. as per post 2 I believe.

 

[micknew]

Not trying to take the P Mick, are you new to the noble art of electrickery?

 

[trev]

And to be fair to us we're always up for a bit of sport, it's just your poor luck that you were it tonight. Don't worry though it'll be someone else tomorrow and pretty soon you'll be joining in with us. We don't mean to be nasty, it's all Tel's fault he made us do it

 

[telectrix]

The conductive part you're touching has to be connected to earth for current to flow. as per post 2 I believe.

or to neutral.

 

[m1ck_b87]

The conductive part you're touching has to be connected to earth for current to flow. as per post 2 I believe.

So when you test across live and earth to measure voltage current flows or is it giving the current potential to flow

 

[micknew]

And to be fair to us we're always up for a bit of sport, it's just your poor luck that you were it tonight. Don't worry though it'll be someone else tomorrow and pretty soon you'll be joining in with us. We don't mean to be nasty, it's all Tel's fault he made us do it

We have to do as Tel says!

 

[Marvo]

When you test across live and neutral it measures the voltage difference between the two wires and only a very small current flows through the tester because it has a very high internal resistance.

 

[telectrix]

when you test from L to E, a current flows through the meter. if your meter is set to volts, then it will read the voltage , or potential difference between L and E. obviously, the meter is high resistance, so the current through it is small ( mA ).

 

[m1ck_b87]

Yeh makes more sense now

 

[markythesparky]

The voltage at each of the birds feet is the same sitting on hv cables. Voltage is the energy that 'pushes' current or as some one once said to me, the pressure. If there is no potential difference (voltage) between the birds legs then there is no way that current will flow. There is no pressure to push it.
Incidentally if you find that your bird has voltage between her legs, be very careful. There is a thread on here showing what could happen and it's very funny.

 

[ipf]

The voltage at each of the birds feet is the same sitting on hv cables. Voltage is the energy that 'pushes' current or as some one once said to me, the pressure. If there is no potential difference (voltage) between the birds legs then there is no way that current will flow. There is no pressure to push it.
Incidentally if you find that your bird has voltage between her legs, be very careful. There is a thread on here showing what could happen and it's very funny.

It shows she hasn't thrown her toy out of the bed.

 

[markc123]

...or to be blunt - it shows she's a ----.

Good night all

 

[odawire]

Extremely Dangerous job! High Power Line Worker - YouTube