PHYS175 Final

In which of these cases will a ripe banana appear black: when illuminated with red, yellow, green, or blue light? Explain.

The banana will appear black when illuminated by blue light. Blue light doesn't produce any yellow light and a banana only reflects yellow light, therefore it won't reflect any colors making it appear black.

What part of the atom does the Earth represent and why?

The earth represents the electrons, as they are orbiting around the protons and neutrons.

What part of the atom does the Sun represent and why?

The protons and neutrons, as they are the nucleus of the solar system

How could you use the spotlights at a play to change the performers' clothes suddenly from yellow to black? Explain.

The spotlight would first be white so the shirt appears to be yellow. If the spotlight is colored blue, it would make the clothing appear black. Yellow + Blue would make it appear black.

Does light travel faster through the lower atmosphere or through the upper atmosphere? Explain.

The upper atmosphere has less density than lower atmosphere, as it has less air molecules than the lower atmosphere. Because there are less particles to travel through, light would travel faster in the upper atmosphere than the lower atmosphere.

Describe why ultraviolet light, but not infrared light, is effective in making certain materials fluoresce.

There is more energy per photon in ultraviolet light.

Rank each of the following from smallest to greatest speed in a vacuum: yellow light, x rays, ultraviolet, microwaves, green light, infrared.

These are all electromagnetic waves. They all have the same speed, but different wavelengths and frequencies.

Describe what ultraviolet and infrared light have in common.

UV and IR have the same wave speed.

Describe what ultraviolet and infrared light do NOT have in common.

UV has a greater frequency, photons with greater energy, and smaller wavelength than IR.

Rank each of the following from smallest to greatest wavelength: yellow light, x rays, ultraviolet, microwaves, green light, infrared.

X Rays, Ultraviolet, Green Light, Yellow Light, Infrared, Microwaves

rank each of the following from smallest to greatest period: yellow light, x rays, ultraviolet, microwaves, green light, infrared.

x rays, ultraviolet, green light, yellow light, infrared, microwaves

Your friend reasons that magenta and yellow paint mixed together will produce red because magenta is a combination of red and blue and yellow is a combination of red and green—and that the color in common is red. Do you agree or disagree, and why?

Disagree. Red is a primary color and cannot be produced by mixing.

Green light is emitted when electrons in a substance make a particular energy-level transition. If blue light were instead emitted from the same substance, would it correspond to a greater or lesser change of energy in the atom? Explain.

Greater because blue has more frequencies.

rank each of the following from smallest to greatest frequency: yellow light, x rays, ultraviolet, microwaves, green light, infrared.

Microwaves, Infrared, Yellow Light, Green Light, Ultraviolet, X Rays

How can a hydrogen atom, which has only one electron, have so many spectral lines? Explain.

One electron can be boosted to many different energy levels.

Does sound faster through the lower atmosphere or through the upper atmosphere? Explain.

Sound travels faster through the lower atmosphere than the upper atmosphere. The upper atmosphere has a lower air temperature than the lower atmosphere, and sound travels slower through low temperatures. Therefore, sound would travel faster through the lower atmosphere where temperatures are higher than the upper atmosphere.