# Physics

posted by .

I am confused as to how light would work in the following question:

Some very efficient streetlights contain sodium vapour under high pressure. They produce light that is mainly yellow with some red. Should a community having these lights buy dark blue police cars? Why or why not?

I'm guessing that the lights would make the cars look yellow???

• Physics -

If the police cars looked yellow, that means they are reflecting yellow light. Does blue reflect blue? What happens to yellow light on a blue surface. Why is grass green?

I will be happy to critique your thinking.

As a side note, yellow green is becoming a very popular color for fire engines. This is because....

• Physics -

So the cars will reflect blue light, but since no blue light is being emitted, they won't look blue? Since yellow light is a combination of red and green light, no blue is involved. One will not be able to see the police cars???

Thank you for your help!! :)!

• Physics -

excellent reasoning.

• Physics -

Thank you for your help! :)

## Similar Questions

1. ### check/bio!!!!

okay the question is as follows: Three plants are placed in 3 different terrariums in 3 different light conditions. Plant A is placed in blue light, plant B in green light, and plant C in yellow light. In which case will there be an …
2. ### Physical Science

I need help with some of these questions: 1.If you look at a red leaf, what describes what happens when you see it?
3. ### Physics - light

1. Blue light and yellow light combine to produce white light because they constructively interfere. Explain why 2. You shine yellow light on an object and it appears black. What color might the object be if illuminated by red light?
4. ### Physics

A person driving her car at 54 km/h approaches an intersection just as the traffic light turns yellow. She knows that the yellow light lasts only 2.0 s before turning to red, and she is 30 m away from the near side of the intersection. …
5. ### Physic

A sodium-vapour lamp illuminates, with monochromatic yellow light, two narrow slits that are 1.00 mm apart. if the viewing screen is 1.00m from the slits and the distance from the central bright line to the next bright line is 0.589 …
6. ### chemistry ........................chemistry

Sodium Na+ Intense yellow Barium Ba++ Green Calcium Ca++ Brick red Copper Cu+ or Cu++ Blue-green Strontium Sr++ ?
7. ### Physics

Which of the following is correct for the two coherent light waves to produce zero light?
8. ### physics

A person driving her car at 56km/hr approaches an intersection just as the traffic light turns yellow. She knows that the yellow light lasts only 20.s before turning to red, and she is 30m away from the near side of the intersection. …
9. ### Chemistry

Sodium vapor lamps are often used in residential street lighting. Sodium gives off two yellow lines of light having frequencies of 5.09 × 1014 Hz and 5.08 × 1014 Hz. What is this wavelengths of light in nm?
10. ### Physics

A person driving her car at 45km/h approaches an intersection just as the traffic light turns yellow. She knew that the yellow light lasts only 2s before turning red,and shi is 28m away from the near side of the intersection. Should …

More Similar Questions