Why does electricity appear blue but sparks from electricity are yellow-ish Orange

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Driving down the road yesterday they were repairing some electrical lines and I guess one of them sparked and it left a trail of blue sparks on the ground. But when I hook up a battery and short it with a wire sparks appear an orangish-yellow color.

Anyone know why?

In: Engineering

15 Answers

Anonymous 0 Comments

Sparks are, generally, not actually the electricity itself. Instead, they are small slivers of super-heated metal. The color is dependant on heat.

Now, sometimes it is electricity jumping from the source to a grounded object. In these cases, it will primarily be a flash of white light, but may tint blue depending on atmospheric conditions.

Edit: To clarify, the white and blue is the air super-heating, not electricity itself. You *might* see it go into the reds, but it is less likely.

Anonymous 0 Comments

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Anonymous 0 Comments

None of the answers so far have correctly mentioned the reason why electricity often appears blue. Electrical sparks are a result of ionizing the nitrogen in the air, which glows violet. It’s the same phenomenon that makes neon tubes glow.

The yellow and orange sparks you see are little bits of hot metal flying off whatever the electricity is burning up.

Anonymous 0 Comments

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Anonymous 0 Comments

The electricity itself isn’t blue, per se. It’s the ionization of Nitrogen in the air that makes it look that way. When you burn metals or create a spark, you aren’t ionizing Nitrogen in the air, instead you are burning the material that caused the spark, which is going to burn a different color.

That’s about as ELI5 as I could get lol.

Anonymous 0 Comments

When you add electrical energy to a gas, it gets excited. Basically the electrons jump up to another energy level. When they come down to their natural resting level, that energy has to go somewhere, so the electrons emit photons. This is known as fluorescence and it’s also how fluorescent lights work.

Depending on what has all that extra energy, you get different colors of light. Excited air (nitrogen, oxygen, etc.) just happens to fluoresce in that iconic electric blue.

What you experience as sparks from electricity in your case has 2 causes. First of all, the sparks that fly off and glow orange are actually burning metal. Not molten. Burning. When metal is sitting at rest, it has a thin oxidation layer. In steel and iron it’s a thin coating of rust. Other metals also have it. When you knock some of that metal off with a decent amount of energy (like enough to ignite it) it immediately reacts with oxygen and burns, glowing bright briefly. In the case of a high tension line transformer or a car battery, there’s a ton of amperage involved. Add enough amperage, and some of that metal is going to fly off from the sudden flow of energy.

Otherwise, the sparks you see from the wire as it arcs to the terminals of the battery are the same as lightning, but they have another component that changes the color of the arc. Some of the wire is actually shooting off the end, over the arc, and onto the terminal. It’s also how arc welding works. The presence of the metal actually changes the composition, and thus the color of the arc.

Anonymous 0 Comments

The reason “electricity” is blue is because it ionises the nitrogen in the air, and when the atoms go back to a lower energy state, they shoot photons out.

The reason sparks are orange is because they’re not electricity, they’re just superheated bits of metal.

Anonymous 0 Comments

Sparks are just hot pieces of things (usually metal), and they just happen to be glowing in that temperature range to produce red to white light. “Electricity” is that white/blue/sometimes purpleish color when it arcs because it’s actually turning certain elements in the air into a plasma. The arc is so hot it’s ripping electrons off the atoms, ionizing the gas, and the color light it gives off (called it’s emission spectrum) is that bright blue color.

Anonymous 0 Comments

No, not quite.
Ionization of the air causes the blueish sparking. Orange, yellow or other sparks are from the metal conductors used.

Its the same sort of thing used in fireworks – certain chemicals and compounds give a particular flame.

Its really as straightforward as that.

Anonymous 0 Comments

Electricity doesn’t have a color. Light is made of tiny particles called photons, while electricity is made of electrons. When you “see” electricity, you are seeing a side effect of electricity, not the electricity itself. When electricity moves in outer space, where there is nothing for it to interact with, it is invisible!

When you see sparks or lightning on earth, you are seeing ionized air created by electricity. Ionized oxygen and nitrogen glow a blueish color, and together oxygen and nitrogen make up about 99% of the atmosphere. If Earth’s atmosphere was made of a different gas, sparks and lightning would be a different color! For instance a planet with an atmosphere made mostly of Neon would have bright red lightning!

When you see red or yellow “sparks” caused by electricity (such as coming off an electric welder or the explosion of an electric transformer), you aren’t seeing electricity, but tiny pieces of metal heated up to red or yellow hot. Electricity heated these pieces up and caused them to break off and fly away, but the electricity is invisible. You can see similar sparks come from non-electrical causes such as a flint/steel fire lighter, or metal being ground with abrasives.

There is another type of electricity-to-light effect you see every day but might not notice: light bulbs! There are several types of electric lights. In none of them do you “see” electricity, only its side effects.

1. Old fashioned incandescent bulbs – these work by heating up a wire to be very very hot, so that it glows yellow white. There is a protective glass bulb around the wire filled with gas that prevents the wire from burning up.

2. Arc bulbs – these work almost like lightning! Electricity flows through a gas inside the bulb and ionizes the gas, creating light. Different gasses glow different colors. White fluorescent lamps are a special type of arc bulb. Another common type are the yellowish bulbs used in some street lamps, which are filled mostly with sodium gas, which glows yellow when ionized.

3. LED light bulbs are the newest type and are becoming more common. They use a special type of chip like in a computer that converts electrical energy to light energy. The electricity flows through the chip invisibly, the light is emitted by the chip due to complicated physics that are beyond ELI5.