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Is it reliable to hide in the car against lightning?

With the advent of summer, lightning will show its prestige on the weather stage again. When you encounter lightning outdoors, you’d better hide in a closed car. Then, the question comes: why can cars protect against lightning? Is it really an ideal place to avoid lightning?

Is the car intact after being struck by lightning& nbsp;
Many people may have seen such a live video: a car sped along the highway in a thunderstorm and was suddenly hit by a lightning bolt from the sky. What is more surprising is that the car struck by lightning can still continue to drive unharmed. Another search from the Internet will find that there is more than one similar video. It can be seen that cars are not afraid of lightning is really not an accident.
On this issue, the famous automobile program topgear once conducted a crazy experiment of lightning struck cars: the host sat in a Volkswagen Golf Car and shocked the car with 600000 v high voltage through the high voltage discharge device to simulate whether the car would hurt the driver and passengers when it was struck by lightning. The experiment showed that after receiving the high-voltage electric shock, only the indicator light of the instrument panel of the vehicle was affected, other instruments were normal, the body was not hurt at all, and the host sitting in the car was safe and sound. From the experiment of topgear, we can see that the car is really “not afraid” of lightning, and the passengers in the car will not be hurt.
Why? Relevant experts pointed out that this is related to the “Faraday cage” effect.
Faraday cage: a “Golden Bell Jar” against lightning& nbsp;
Cars are “not afraid” of lightning because of the existence of Faraday cage. So, what is Faraday cage?
Faraday cage is a cage made of metal or good conductor. It was invented by Michael Faraday, the founder of electromagnetism and British physicist, and named after him. It is a kind of equipment mainly used to demonstrate the principles of equal potential, electrostatic shielding and high-voltage live working. In 1836, Faraday found that the excess charge on a charged conductor existed only on its surface and would not affect any object enclosed in it. To prove this fact, he built a room with a metal foil shell and shocked the shell of the room through the high voltage of the electrostatic generator. The electroscope showed that there was no excess charge in the room. The metal shell of the room plays a “protective” role in its interior, making it completely unaffected by the change of external electric field. This is the Faraday cage effect. Using this principle, the protective clothing of high-voltage live operators is made of metal wire. When contacting the high-voltage line, equipotential is formed, so that there is no current passing through the operator’s body, which plays a good protective role.
At this point, it is not difficult to understand the reason why we are not afraid of lightning strikes. The conditions for making a Faraday cage are very close to that of a car shell. With this “iron cloth shirt”, when the driver is driving in a thunderstorm, even if he is unfortunately hit by lightning, due to the Faraday cage effect, the electromagnetic environment inside the car is basically not affected, and the people in the car can stay inside safely. At the same time, the lightning current will reach the position of the axle through the surface of the vehicle body with the help of rainwater, and the current will be transmitted to the ground quickly through the wet tire. Therefore, the interior of the vehicle is an ideal lightning protection place outdoors.
Faraday cage has also been well used in aircraft lightning protection and building lightning protection. According to statistics, every aircraft in normal operation is struck by lightning almost once a year, but most of them will not lead to disastrous consequences. This is mainly because the current commercial aircraft shell is made of metal materials, which has a good shielding effect against lightning, and the personnel and equipment inside the aircraft are relatively safe. High rise buildings are easy to be struck by lightning, and the cage lightning protection network made by using the principle of Faraday cage can effectively reduce the harm caused by lightning to human body. For example, in the “bird’s nest” of the National Stadium, the steel members in its main steel structure and the reinforcement in reinforced concrete are effectively connected by welding, so that the “bird’s nest” itself forms a huge lightning protection network, and the steel structure of the “bird’s nest” becomes a huge lightning receiving device, which can quickly lead lightning into the ground, So as to ensure the safety of the audience.
However, it should be noted that the outdoor lightning protection of cars and aircraft is not absolutely safe. When the car is hit by lightning, the instantaneous high-voltage electricity may also damage the electronic components in the car, resulting in the electrical equipment in the car can not work normally, and in serious cases, there will be a fire. In addition, the metal parts of the vehicle roof and wheels may leave scars after being struck by lightning.
How to drive safer in lightning weather& nbsp;
Through the introduction above, we know that even if the car body can form the “golden bell cover” of Faraday cage, we can’t drive recklessly in thunderstorm weather. The following points still need attention.
In case of lightning and thunder during driving, it is best to park the car at a safe place on the roadside in time, away from trees, billboards, etc., turn off the engine, sound system, radio, etc., and close all windows to make the car form a completely enclosed space. Don’t touch the window handle, gear lever, steering wheel, etc. put your hands on your thighs and wait for the lightning weather to stay away.
If the car is struck by lightning on the way, you must not get off the car to check the condition of the car, because it is much more dangerous outside the car than inside the car at this time. Instead, we should refer to the practice described above and wait until the thunderstorm is completely over before getting off.
The last thing to say is that if you listen to the weather forecast in advance and know that there will be thunderstorms, you should drive less or don’t drive as much as possible and go out when the weather is good. This is the most reliable way to avoid lightning and ensure safety.