Would Headlights Work At The Speed Of Light?

What do you think?

AT 186,000 miles per second things might be a lot different. The ever adventurous YouTUber who goes by the name of “VSauce” often asks some unusual questions and then engages in a scientific fact finding mission. In this case he wants to know would your car headlights work if the car was traveling at the same speed of the lights themselves?

What do you think?

The exact speed of light is:

299 792 458 m/s (in the metric system)

Just a note this refers to light traveling in a vacuum although there probably wouldn’t be a huge difference in a regular atmosphere.

Let’s find out the answer in the video on page 2

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  1. Bill Ness said:

    The question isn’t logical. Light is going the speed of light only in a vacuum. It doesn’t matter what is emitting it, or what speed that emitter is going. What matters is the relativity of the viewer. Whether the viewer is riding the light beam or is viewing beams from a stationary position, the light is still going at the speed of light to the viewer.

  2. Ronny Field said:

    If you are driving the speed of light and hit the headlights, the light will not illuminate in front of the car. The car and the light are equal in speed

  3. Colleen Conway said:

    Light is a cosmological constant, hence the “C” in E=MC2 Light will jet away at the speed of light from the viewpoint of the observer. That’s Einstein’s relativity.

  4. Mike Guay said:

    Not according to our current understanding. Light cannot go faster than itself. There are a couple quantum processes that appear to be faster than light.

  5. Mike Guay said:

    Yeah, you can’t add the speed of light to the speed of light to create a super fast FTL wave/particle.
    Not under physics as we currently understand it today.

  6. JuStin Spear said:

    Lets look at it this way… lets say light speed is 65mph… also lets say white car next to you is light, driving at light speed (65MPH). you are also driving at 65mph… is light moving any faster than you? No, because you are also moving at light speed. 😉

  7. Jeff Walters said:

    Yes, but you are actually stationary but time is moving a lot slower for you so instead of increasing speed you’re slowing down time in your dimension. So if you’re observing a light speed traveler from earth, it’s just a matter of perspective.

  8. Sandra Hall said:

    I think this is just my thoughts. That seeing light then traveling the speed of light would be like riding a wave. So there would be light next to you and behind you but not in front of you. The same with headlights

  9. Sandra Hall said:

    Here’s one if you’re driving down the road 100 mph. You toss a ball in the air it stays right in front of you. So in theory its traveling 100mph while in the air in the car as soon as you throw it out of the car it stops traveling 100 mph why is that?

  10. John Brough said:

    Its relative as Einstein said its like throwing a ball in a jet doing 600 mph the ball moves relative to the jet so it is only traveling at the speed you throw it

  11. Al Arruda said:

    This has been answered many times. The headlights still shine. You can’t overtake light. It may be counter intuitive if you’re thinking only Newtonian rules, which is why Einstein had to explain relativity to everybody.