If you're reading this too fast, the text will be purple...

[Luis G]

Yes, and no, . Read it once more, and don't think about cars...

So it has to be blue as in "gone" right?

 

[BlurOfSerenity]

i am so lost

 

[Nixy]

So it has to be blue as in "gone" right?

Blue doesn't mean gone...

 

[IDLEchild]

i am so lost

Ash it is easy....though not practical in the case of a fast moving car...thats why it was a joke

Observers looking at an object that is moving away from them see light that has a longer wavelength than it had when it was emitted (a redshift), while observers looking at an approaching source see light that is shifted to shorter wavelength (a blueshift).

So if you're approaching the car the joke is that the wavelength is shifting to blue.

 

[Inkara1]

I thought maybe the sticker was a member of the Sierra Club and firmly believed that driving faster than 55 is certain death for the planet... so the sticker was sad.

 

[Luis G]

Blue doesn't mean gone...

Kinda out of the blue, not gone, but like empty, isn't it?

 

[Inkara1]

"Out of the blue" means "out of nowhere," as in, "surprisingly."

"I was just standing there, minding my own business, when out of the blue a low-flying 747 knocked me in the back of the head."

 

[Luis G]

Then I have no idea what the sticker meant

 

[Professur]

So, ready to let them in on the joke, Gato?

 

[Luis G]

It has to do with the wave-length of light as you approach the speed of light. Unfortunately, in that application, it doesn't apply. Not just for your observation either. The mass-to-energy conversion rate to get a common automobile up to that speed is too great for todays technology.

Doppler effect.

Should have known before but perhaps I was reading too much into the words.