What voltage and amps are and why high volts may not kill you but high amps will
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If it helps, think of voltage as the “desire” for electricity to get from one place to another, and amps as how much work we can make that electricity do along the way.
High voltage will try really hard to get from where it starts to where it wants to go. (This is a simplification, bordering on inaccurate, but it is a way to visualize it.) Low voltage will move, but will not try as hard. On a side note, this is why we use high voltage to move electricity long distances.
Amps are what we use to do work. A 2 amp light will be much brighter than a 1 amp light, at the same voltage. If something happens, and the available number of amps drops to 0.5 amps, then those lights will go dim (and the 2 amp light might not shine at all).
High voltage is a concern because it can go through the human body, where lower voltage would not. The human body has enough resistance that voltages from normal batteries, as you would find in a cell phone, or a petrol-powered (not electric) car, will not pass through the body. Household voltage will, and things that use higher voltage (such as neon or fluorescent lights) will pass through a body even easier. High voltage can also pass through water and other things that are not obvious conductors, and can jump through the air (think of lightning or a Van de Graaff generator, or even just static electricity from rubbing your feet on carpet).
Amps are what does the “work” though. High voltage with no amps behind it will give you a zap or tingle (think of a Taser/stun gun, or electrified fence). With amps, you can weld metal together, burn wood, use a pickle as a light source, or cook meat/flesh. (Or, obviously, do useful work such as produce light, turn motors, power appliances, and run electronics.)
However, high voltage and low amps can still be dangerous in some situations, since the heart uses low amp power to control its beat, and the right/wrong kind of shock across the heart needs to only have a few hundredths of an amp (tens of milliamps) to make the heart stop beating or to keep it from being able to beat correctly.
Meanwhile, low voltage and high amps is not typically dangerous directly. A standard petrol car’s battery provides hundreds of amps, up to a thousand amps. It is completely safe to touch both terminals with your bare hands though. At the same time, there can still be a danger if you touch a piece of metal to both terminals, but that is due to sparks (which can cause fires), heat (enough to burn fingers and such), or explosion (if the battery overheats from discharging too quickly).
Long rambling tirade ahead:
Electrons exist statically in everything. We apply voltage to get them to move. They move through circuits we design to make things happen. However, they move really fast, nearly the speed of light. So when they move they generate heat and tend to blow things up trying to return to the source. So we add resistors. Resistors can take the form of insulation, a load (a fan motor), or… well… resistors in a circuit board. An ampere is actually a specific amount of electrons (6.241509074×10¹⁸ electrons) moving past a point every second.
Think of the relation of voltage to amps like a pressure washer. The pressure washer can move 2 gallons per minute. Increasing the voltage is like closing the valve to make the stream of water thinner, lowering the voltage is like opening the valve wider but It’s moving the same amount of water per minute, that is wattage. Using joules law which is power = voltage X current (amps) we can give some examples. 10 amps at 100 volts gives us 1000 watts, 1 amp at 1000 volts gives us 1000 watts, 100 amps at 10 volts gives us 1000 watts.
Now since moving electrons create heat, we need bigger conductors to hold more electrons in any given part of the conductor. A 14 gauge copper wire is rated for 15 amps continuous. Too much more than that for too long and the wire will heat up and possibly melt the insulation and catch fire and melt the conductor. Conductor size is strictly a limit on the amperage that can pass through the wire. The insulation limits the how far the current can reach out away from the conductor to other things we don’t want energized. Insulation just serves as a barrier to isolate the conductor from its surroundings (and can be dyed to color code conductors) and different insulators are rated for different voltages and installation conditions. Air is a decent and inexpensive insulator and that’s why we have 500kv lines high up in the air. If you were to look up a 4/0 wire on google you’ll see that it’s not tooo much smaller than the lines that hang in your neighborhood. Well your house may have a 200 amp main breaker and that 4/0 AL is good for a 200 amp service. So how do those little lines power this whole street?
That’s where transformers come in. Transformers step down the voltage from the primary (the power lines) to the secondary (your house). Increasing the voltage means you can push more amps through the same size wire and service more customers. That 200 amps at 120 volts (which you’ll probably never actually reach) is actually only like 0.8 amp I wanna say? There’s also a good chance the wire size above you is around 500 kcmil copper which is rated for 320 amps. At 30kv that’s 509 kcmil wire can service 400 homes pulling 200 amps 120v each. Again that’ll never happen. Sorry for the long rant.
But to answer your actual question. Your skin is an insulator and resists low voltages. I’ve experienced about 50v and barely felt it. I touch low 24-30v with bare fingers all the time and don’t feel it. It’s only when the voltage is high enough to overcome your bodies (and shoes) resistance that things become deadly. It takes comparatively minuscule amount of current to actually kill you as you’ve read in the comments by now, I was messing with a fridge the other day and it only pulled 1.5 amps. That’s a pretty tiny amount of current and is also like like 7x more then enough current to kill you.
If it helps, think of voltage as the “desire” for electricity to get from one place to another, and amps as how much work we can make that electricity do along the way.
High voltage will try really hard to get from where it starts to where it wants to go. (This is a simplification, bordering on inaccurate, but it is a way to visualize it.) Low voltage will move, but will not try as hard. On a side note, this is why we use high voltage to move electricity long distances.
Amps are what we use to do work. A 2 amp light will be much brighter than a 1 amp light, at the same voltage. If something happens, and the available number of amps drops to 0.5 amps, then those lights will go dim (and the 2 amp light might not shine at all).
High voltage is a concern because it can go through the human body, where lower voltage would not. The human body has enough resistance that voltages from normal batteries, as you would find in a cell phone, or a petrol-powered (not electric) car, will not pass through the body. Household voltage will, and things that use higher voltage (such as neon or fluorescent lights) will pass through a body even easier. High voltage can also pass through water and other things that are not obvious conductors, and can jump through the air (think of lightning or a Van de Graaff generator, or even just static electricity from rubbing your feet on carpet).
Amps are what does the “work” though. High voltage with no amps behind it will give you a zap or tingle (think of a Taser/stun gun, or electrified fence). With amps, you can weld metal together, burn wood, use a pickle as a light source, or cook meat/flesh. (Or, obviously, do useful work such as produce light, turn motors, power appliances, and run electronics.)
However, high voltage and low amps can still be dangerous in some situations, since the heart uses low amp power to control its beat, and the right/wrong kind of shock across the heart needs to only have a few hundredths of an amp (tens of milliamps) to make the heart stop beating or to keep it from being able to beat correctly.
Meanwhile, low voltage and high amps is not typically dangerous directly. A standard petrol car’s battery provides hundreds of amps, up to a thousand amps. It is completely safe to touch both terminals with your bare hands though. At the same time, there can still be a danger if you touch a piece of metal to both terminals, but that is due to sparks (which can cause fires), heat (enough to burn fingers and such), or explosion (if the battery overheats from discharging too quickly).
Long rambling tirade ahead:
Electrons exist statically in everything. We apply voltage to get them to move. They move through circuits we design to make things happen. However, they move really fast, nearly the speed of light. So when they move they generate heat and tend to blow things up trying to return to the source. So we add resistors. Resistors can take the form of insulation, a load (a fan motor), or… well… resistors in a circuit board. An ampere is actually a specific amount of electrons (6.241509074×10¹⁸ electrons) moving past a point every second.
Think of the relation of voltage to amps like a pressure washer. The pressure washer can move 2 gallons per minute. Increasing the voltage is like closing the valve to make the stream of water thinner, lowering the voltage is like opening the valve wider but It’s moving the same amount of water per minute, that is wattage. Using joules law which is power = voltage X current (amps) we can give some examples. 10 amps at 100 volts gives us 1000 watts, 1 amp at 1000 volts gives us 1000 watts, 100 amps at 10 volts gives us 1000 watts.
Now since moving electrons create heat, we need bigger conductors to hold more electrons in any given part of the conductor. A 14 gauge copper wire is rated for 15 amps continuous. Too much more than that for too long and the wire will heat up and possibly melt the insulation and catch fire and melt the conductor. Conductor size is strictly a limit on the amperage that can pass through the wire. The insulation limits the how far the current can reach out away from the conductor to other things we don’t want energized. Insulation just serves as a barrier to isolate the conductor from its surroundings (and can be dyed to color code conductors) and different insulators are rated for different voltages and installation conditions. Air is a decent and inexpensive insulator and that’s why we have 500kv lines high up in the air. If you were to look up a 4/0 wire on google you’ll see that it’s not tooo much smaller than the lines that hang in your neighborhood. Well your house may have a 200 amp main breaker and that 4/0 AL is good for a 200 amp service. So how do those little lines power this whole street?
That’s where transformers come in. Transformers step down the voltage from the primary (the power lines) to the secondary (your house). Increasing the voltage means you can push more amps through the same size wire and service more customers. That 200 amps at 120 volts (which you’ll probably never actually reach) is actually only like 0.8 amp I wanna say? There’s also a good chance the wire size above you is around 500 kcmil copper which is rated for 320 amps. At 30kv that’s 509 kcmil wire can service 400 homes pulling 200 amps 120v each. Again that’ll never happen. Sorry for the long rant.
But to answer your actual question. Your skin is an insulator and resists low voltages. I’ve experienced about 50v and barely felt it. I touch low 24-30v with bare fingers all the time and don’t feel it. It’s only when the voltage is high enough to overcome your bodies (and shoes) resistance that things become deadly. It takes comparatively minuscule amount of current to actually kill you as you’ve read in the comments by now, I was messing with a fridge the other day and it only pulled 1.5 amps. That’s a pretty tiny amount of current and is also like like 7x more then enough current to kill you.
If it helps, think of voltage as the “desire” for electricity to get from one place to another, and amps as how much work we can make that electricity do along the way.
High voltage will try really hard to get from where it starts to where it wants to go. (This is a simplification, bordering on inaccurate, but it is a way to visualize it.) Low voltage will move, but will not try as hard. On a side note, this is why we use high voltage to move electricity long distances.
Amps are what we use to do work. A 2 amp light will be much brighter than a 1 amp light, at the same voltage. If something happens, and the available number of amps drops to 0.5 amps, then those lights will go dim (and the 2 amp light might not shine at all).
High voltage is a concern because it can go through the human body, where lower voltage would not. The human body has enough resistance that voltages from normal batteries, as you would find in a cell phone, or a petrol-powered (not electric) car, will not pass through the body. Household voltage will, and things that use higher voltage (such as neon or fluorescent lights) will pass through a body even easier. High voltage can also pass through water and other things that are not obvious conductors, and can jump through the air (think of lightning or a Van de Graaff generator, or even just static electricity from rubbing your feet on carpet).
Amps are what does the “work” though. High voltage with no amps behind it will give you a zap or tingle (think of a Taser/stun gun, or electrified fence). With amps, you can weld metal together, burn wood, use a pickle as a light source, or cook meat/flesh. (Or, obviously, do useful work such as produce light, turn motors, power appliances, and run electronics.)
However, high voltage and low amps can still be dangerous in some situations, since the heart uses low amp power to control its beat, and the right/wrong kind of shock across the heart needs to only have a few hundredths of an amp (tens of milliamps) to make the heart stop beating or to keep it from being able to beat correctly.
Meanwhile, low voltage and high amps is not typically dangerous directly. A standard petrol car’s battery provides hundreds of amps, up to a thousand amps. It is completely safe to touch both terminals with your bare hands though. At the same time, there can still be a danger if you touch a piece of metal to both terminals, but that is due to sparks (which can cause fires), heat (enough to burn fingers and such), or explosion (if the battery overheats from discharging too quickly).
Long rambling tirade ahead:
Electrons exist statically in everything. We apply voltage to get them to move. They move through circuits we design to make things happen. However, they move really fast, nearly the speed of light. So when they move they generate heat and tend to blow things up trying to return to the source. So we add resistors. Resistors can take the form of insulation, a load (a fan motor), or… well… resistors in a circuit board. An ampere is actually a specific amount of electrons (6.241509074×10¹⁸ electrons) moving past a point every second.
Think of the relation of voltage to amps like a pressure washer. The pressure washer can move 2 gallons per minute. Increasing the voltage is like closing the valve to make the stream of water thinner, lowering the voltage is like opening the valve wider but It’s moving the same amount of water per minute, that is wattage. Using joules law which is power = voltage X current (amps) we can give some examples. 10 amps at 100 volts gives us 1000 watts, 1 amp at 1000 volts gives us 1000 watts, 100 amps at 10 volts gives us 1000 watts.
Now since moving electrons create heat, we need bigger conductors to hold more electrons in any given part of the conductor. A 14 gauge copper wire is rated for 15 amps continuous. Too much more than that for too long and the wire will heat up and possibly melt the insulation and catch fire and melt the conductor. Conductor size is strictly a limit on the amperage that can pass through the wire. The insulation limits the how far the current can reach out away from the conductor to other things we don’t want energized. Insulation just serves as a barrier to isolate the conductor from its surroundings (and can be dyed to color code conductors) and different insulators are rated for different voltages and installation conditions. Air is a decent and inexpensive insulator and that’s why we have 500kv lines high up in the air. If you were to look up a 4/0 wire on google you’ll see that it’s not tooo much smaller than the lines that hang in your neighborhood. Well your house may have a 200 amp main breaker and that 4/0 AL is good for a 200 amp service. So how do those little lines power this whole street?
That’s where transformers come in. Transformers step down the voltage from the primary (the power lines) to the secondary (your house). Increasing the voltage means you can push more amps through the same size wire and service more customers. That 200 amps at 120 volts (which you’ll probably never actually reach) is actually only like 0.8 amp I wanna say? There’s also a good chance the wire size above you is around 500 kcmil copper which is rated for 320 amps. At 30kv that’s 509 kcmil wire can service 400 homes pulling 200 amps 120v each. Again that’ll never happen. Sorry for the long rant.
But to answer your actual question. Your skin is an insulator and resists low voltages. I’ve experienced about 50v and barely felt it. I touch low 24-30v with bare fingers all the time and don’t feel it. It’s only when the voltage is high enough to overcome your bodies (and shoes) resistance that things become deadly. It takes comparatively minuscule amount of current to actually kill you as you’ve read in the comments by now, I was messing with a fridge the other day and it only pulled 1.5 amps. That’s a pretty tiny amount of current and is also like like 7x more then enough current to kill you.
Voltage (potential) tells you how bad a charged particle wants to go from one side to the other. Current tells you how many of these particles will be going. High current -> Zerg rush
Voltage (potential) tells you how bad a charged particle wants to go from one side to the other. Current tells you how many of these particles will be going. High current -> Zerg rush
Voltage (potential) tells you how bad a charged particle wants to go from one side to the other. Current tells you how many of these particles will be going. High current -> Zerg rush
I use a Bosch hammer drill for my job. A couple of times I was using it in the rain and I could feel a needly sensation throughout my arms. I never to really figured out why.
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