Science Discussion Thread

Hello People..

Created this thread to share & gain some knowledge on science (Physics/Chemistry/Maths etc etc)

Q: Why does a bird sitting on high tension wires doesn't get electrocuted?

Do participate :doublethumb:

Tell that bird to keep a feet on the ground at the same time , I am sure she'll get electrocuted.

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Bird's feet do not conduct electricity quite well. And also , they have no contact with ground or anything with lower potential while sitting(sh1tting) on the high tension wires above your head .

@Rishi: Ok...so the circuit is not complete thats y the birds are not getting shocked...
so, Assume u hold a long aluminium/copper wire (good conductor) and wearing rubber shoes..so if u touch those high-tension wires.will u get Electrocuted?

Zangetsu said:
@Rishi: Ok...so the circuit is not complete thats y the birds are not getting shocked...
so, Assume u hold a long aluminium/copper wire (good conductor) and wearing rubber shoes..so if u touch those high-tension wires.will u get Electrocuted?

I don;t think that'll happen. I've myself touched just once wire directly from wall socket and nothing ever happened. However, I felt shock only when I touched both the wires.

harshilsharma63 said:
I don;t think that'll happen. I've myself touched just once wire directly from wall socket and nothing ever happened. However, I felt shock only when I touched both the wires.

u were wearing slippers & the circuit was not complete.
but when u touched other wires then u get shocked..the same thing is with birds
if a Bird is sitting in one wire (circuit is not completed) so no shock but if at the same time other parallel wires comes in contact with one (on which bird is sitting)
then Bird will get shocked.

when I was a Student I saw two Crows dancing on the floor (they were dying actually) and a group of boys around them watching..
I wondered at that time what happened to them but then later realized they got shocked (as one of the boy standing there told me)

OK...so its clear that circuit is not complete & there is no earthing so u don't get shock.
so, will these principle still hold true if the current passing through the wires is > 25k Volts?

Actually it's not about the circuit getting complete. It's about developing potential difference. Circuit will be completed when both live and neutral wires come in contact with each other though a resistance or short-circuit.

why dont satellites use low freq. e.m.(electromagnetic) waves, cause im sure we can broadcast using them too..
and also today i learnt about ionosphere in college, but how can we send signals in space if they end up reflecting them back? or is it that they refract partially? then why use it? that wil cause a lot of loss? right?

harshilsharma63 said:
Actually it's not about the circuit getting complete. It's about developing potential difference. Circuit will be completed when both live and neutral wires come in contact with each other though a resistance or short-circuit.

Potential Difference is there when a current flows from higher potential to lower potential (+ve to -ve)
its Ohm's law if u say
also if a circuit is not complete then u cant start TubeLights,Bulbs & other electrical appliances

flyingcow said:
why dont satellites use low freq. e.m.(electromagnetic) waves, cause im sure we can broadcast using them too..

They don't have enough energy before they lose it during propagation.
E=hv

flyingcow said:
why dont satellites use low freq. e.m.(electromagnetic) waves, cause im sure we can broadcast using them too..
and also today i learnt about ionosphere in college, but how can we send signals in space if they end up reflecting them back? or is it that they refract partially? then why use it? that wil cause a lot of loss? right?

Reflection occurs when the incidence angle is greater than critical angle. For ionosphere, the critical angle is different for different frequencies/ wavelengths.
www.tpub.com/neets/book10/40e.htm

Zangetsu said:
Potential Difference is there when a current flows from higher potential to lower potential (+ve to -ve)
its Ohm's law if u say
also if a circuit is not complete then u cant start TubeLights,Bulbs & other electrical appliances

What is your point?

harshilsharma63 said:
What is your point?

short-circuit is not a complete circuit
also the current still flow if I m not wrong thru the birds body

Zangetsu said:
short-circuit is not a complete circuit
also the current still flow if I m not wrong thru the birds body

I don't think current flows through the bird as if it would, it would get fried.

The current will only flow when there is a potential difference and the medium is conductor of electrons.
However , in case of birds , the claws and beaks are insulator and therefore no current can pass.

When you touch the earth while holding the nude wire , you'll get heavily electrocuted because of the extensive difference in potential , but if you are wearing insulator and are not in contact with the ground , the difference of potential is lesser , so I think lesser amount of current will pass through for a while.

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BTW , I have a new Question for you guys , I am still wondering about the answer possible .

Q. In what language do Mute and Deaf people ( Deaf and Mute from birth ) think ?? For instance , I think in English most of the time , while communicating with myself.

W

How do birds sit on high-voltage power lines without getting electrocuted? | MIT School of Engineering

@rishi,beaks & claws have nothing to do with this & btw no living thing can be insulator even if some of its body parts can be considered close to an insulator.Bio 101:70% cell is water.

whitestar_999 said:
How do birds sit on high-voltage power lines without getting electrocuted? | MIT School of Engineering

Nice...Helicopter example is good

Once I opened the washing machine & I put my hand inside soap water (I was bare footed) & I got a sudden shock but after I wear rubber slippers I haven't got any shock

Rishi. said:
Q. In what language do Mute and Deaf people ( Deaf and Mute from birth ) think ?? For instance , I think in English most of the time , while communicating with myself.[/B]

in whichever language they are taught in School...might be any language the person learned
bcoz they are not Blind

whitestar_999 said:
How do birds sit on high-voltage power lines without getting electrocuted? | MIT School of Engineering

@rishi,beaks & claws have nothing to do with this & btw no living thing can be insulator even if some of its body parts can be considered close to an insulator.Bio 101:70% cell is water.

So is it just the potential difference , which helps this ?? I mean the body has no role-play at all ??

Zangetsu said:
Nice...Helicopter example is good

Once I opened the washing machine & I put my hand inside soap water (I was bare footed) & I got a sudden shock but after I wear rubber slippers I haven't got any shock

in whichever language they are taught in School...might be any language the person learned
bcoz they are not Blind

I mean how do they hear it in the brain ?? I mean how does it feel like ?

Seems you guys are all well versed in currents and potential differences

have a question for ya'll

If 'current' be regarded as flow of electrons, the direction of flow being +ve to - ve according to conventions, can anybody explain as to how current flows in an AC (alternating current) transmission system.
Take for instance our supply frequency of 50hz, which means we have polarity reversals (+ve and -ve cycles) every 1/50th of a second, from which we can infer that the electron will be oscillating about its mean position back and forth but no net displacement , then how come there is correct flow ?

nikufellow said:
Seems you guys are all well versed in currents and potential differences have a question for ya'll

If 'current' be regarded as flow of electrons, the direction of flow being +ve to - ve according to conventions, can anybody explain as to how current flows in an AC (alternating current) transmission system.
Take for instance our supply frequency of 50hz, which means we have polarity reversals (+ve and -ve cycles) every 1/50th of a second, from which we can infer that the electron will be oscillating about its mean position back and forth but no net displacement , then how come there is correct flow ?

AFAIK , One end of the power source has more number of electrons/negative charges accumulated compared to the other end. This creates a potential difference , and the body tries to balance this .
This happens in both ways, in an AC current.

A reminder : Current is the charge passing through a cross-sectional area per second and what basically keeps on moving back and forth is the fields ( electric and magentic ) .

J

nice thread.....great answers guys..........i like the last one..... :number1:

G

what is happening here?