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I have read a lot of articles and other post relating to what happens when lightning strikes a vehicle or evening a building with metal.

However, I cannot grasp one part. This is when lighting strikes a metallic object like a vehicle and the energy gets dissipated around the metallic body, how is all that energy in essence destroyed.

I know that energy cannot be created nor destroyed, so maybe destroyed is the wrong word. How is the energy not stored in the metallic object? From a scientific point of view, how does all this energy just get "neutralized"

I would also think that a car battery negative terminal is also connected to the vehicle's body. So when lighting strikes on the body the energy from the lighting strike is also travelling through the battery via the negative terminal. The fact the body is metal, electrical current can flow through it. How does the battery not blow up?

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    \$\begingroup\$ "Dissipated" means "spread out", not "neutralized". E.g. smoke dissipates in the atmosphere. Even when energy dissipates in a resistor, it doesn't go away, it spreads out into the air. \$\endgroup\$ Dec 4, 2020 at 15:42

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The car's metallic frame stays charged and the insides stay safe via the Faraday cage until it can leak away through the tires into the ground.

If you charge both terminals of the 12V battery go up the same amount when measured relative to some third, external reference potential so they both follow each other (say rise by 1000V so there is 1000V on the negative terminal and 1012V on the positive terminal) nothing big happens. That's different than charge flowing through the battery to give you 0V on one terminal and 1012V on the other.

Like your legs. If I lift both your legs up 1000m you're probably okay. If I lift up only one of your legs 1000m you're probably not so okay.

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  • \$\begingroup\$ So, hypothetically speaking. Let's say the car metallic frame is raised of the ground using a perfect insulator that cannot leak any charge through. The car now gets struck my lighting. If I now go and touch the car with bare feet, this means all of that charge now flows through me to the ground (the earth's ground), right? \$\endgroup\$
    – JoeyB
    Dec 4, 2020 at 15:33
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    \$\begingroup\$ @Joey If you're outside the car, yes. That's why you don't just grab a cable dangling from a helicopter as its rotor blades rub against the air to produce static. \$\endgroup\$
    – DKNguyen
    Dec 4, 2020 at 15:33
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    \$\begingroup\$ @Joey I've been told that since junior high. \$\endgroup\$
    – DKNguyen
    Dec 4, 2020 at 15:40
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    \$\begingroup\$ The lightning strike just jumped through miles of air in a fraction of a second. The last 10 inches from chassis to the ground aren't going to last long. It's probably pretty close to discharged in a few milliseconds. The arc that enters the car should ionize a path through it to the Earth. \$\endgroup\$ Dec 4, 2020 at 16:10
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    \$\begingroup\$ @Joey If you're close enough to touch a car that's been hit by lightning within seconds of the strike, you're going to be picking yourself up of the ground wondering why you've gone deaf, and where your eyebrows have gone. \$\endgroup\$
    – Neil_UK
    Dec 4, 2020 at 16:52

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