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Physics - Help me now :P (1 Viewer)

undalay

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In a household with 240 volts AC main.

A television is connected; it draws 1A.

Lets say the television is not functioning properly and shocks all that touches it.

Human fingers with 500, 000 ohmz of resistances does touch this.


How much current will flow through the body ?
 

z600

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an ohmic resistor is one that follows ohm's law. An non-ohmic resistor is one that doesnt, e.g a light bulb, the heat in the tungsten have an effect on the resistor of the light bulb.
 

nelses

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Well I'm not too sure, but most TVs use step up transformers as they need high voltage (in turn decreasing current) to accelerate the electrons in producing light energy. Plus, most electric shocks that kill people are caused by the amps, even 1 amp has the potential in causing fatal damage.

I'm merely taking a guess but I'd say about 0.01 amps would cause an electric shock.
 
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simonloo said:
Friend says depends if its ohmic.
This is your memory, or an actual person, what, chatting with you, from whom you seek answers to the riddles of life?
If it's the former, I'm impressed; you should have stuck with sciences - at least the physical ones!
Btw, sport is off, if you get the chance to read this.

Okay, the given data:
V = 240
I = 1A
R = 5 . 105

Ohm's Law is given by: V = IR, so if you substitute the values into the formula...
you get whatever you get; it should turn out to be 4.8 . 10-4.
 

undalay

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Sorry guys, i figured it out. The current that the appliance draws is irrelevent. Only the voltage matters -__-, even though the mains supply is 240volts AC, we can't determine the actual voltage of the appliance as appliances have transformers in them... Tv screen has 10,000 volts (supposedly)
 
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undalay said:
Sorry guys, i figured it out. The current that the appliance draws is irrelevent. Only the voltage matters -__-, even though the mains supply is 240volts AC, we can't determine the actual voltage of the appliance as appliances have transformers in them... Tv screen has 10,000 volts (supposedly)
Ooh... thanks, undalay.

The school that I attend has yet to start that stuff, I think; we're only up to electric fields, and my class just did Coulomb's law (which one could say is a derivative of Newton's law of gravitation) yesterday. I was v. confused.


Question: What colour is a spark? Does it even have a colour?
What colour is lightning?
 

undalay

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Hmm not sure about the colours, i would think it works with similar principals to flames. What colour is a flame? Depends on the gases it ionizes? not sure once again.
 

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