# Moving at the speed of light

• gary350
In summary, the question of whether or not headlights would still work if a car could travel at the speed of light is impossible to answer with current understanding of physics. However, if the car is traveling at a speed close to the speed of light, the headlights would still work as the car and its components are considered to be stationary.

#### gary350

If my car can travel the speed of light will the head lights still work?

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gary350 said:
If my car can travel the speed of light will the head lights still work?
It's impossible to answer that question because we'd have to use the laws of physics to work out the answer, and if the laws of physics are right then nothing can travel at the speed of light. So either those laws are wrong, in which case we can't trust them to answer your question; or they are right, in which case they can't be applied.

There is a similar question that does make sense though: If you car is traveling at a speed very close to the speed of light (not "at the speed of light") down the road, will the headlights still work? Yes. As far as the car, the driver, the headlights, the car's electrical system are concerned, the car is sitting still while the road underneath it is moving backwards; and there's no reason why that should affect the operation of the headlights.