What makes it possible to see a beam of light

Hanley Rd, Suite St. Louis, MO Subject optional. Email address: Your name:. Example Question 11 : Light And Visibility. What would happen if you put a mirror in front of a laser light? Possible Answers: The light would be reflected. Correct answer: The light would be reflected. Explanation : When a mirror is placed in front of a light source, it will reflect the light or cause it to be bounced back. Report an Error. Example Question 12 : Light And Visibility. What would happen if you put a piece of plastic wrap in front of a flashlight?

Possible Answers: The light would be blocked. Correct answer: The light would pass through. Explanation : If you put a piece of plastic wrap in front of a flashlight, there would be little change because the light would pass through. Example Question 13 : Light And Visibility. What would happen if you put a sheet of black construction paper in front of a flashlight?

Possible Answers: It would allow the light to pass through. Correct answer: It would block the light. Explanation : If you tried to shine a flashlight through a sheet of black construction paper, it would block the light. Example Question 14 : Light And Visibility. If I place a chocolate bar in a beam of light from the Sun, what would the result be?

Possible Answers: Nothing would happen. Correct answer: It would melt. Explanation : If I were to place the chocolate bar in the Sun, it would melt due to the heat. Example Question 15 : Light And Visibility. Possible Answers: Shadows are made by bright lights mixing with dim lights. Shadows are made by cold air and warm air mixing. Correct answer: Shadows are made by blocking light.

Explanation : A shadow is created by blocking light. Example Question 16 : Light And Visibility. The more you try to narrow down the beam width of a wave, the more it will tend to spread out as it travels due to diffraction.

This is true of water waves, sound waves, and light waves. The degree to which a light beam diffracts and diverges depends on the wavelength of the light. Light beams with larger wavelengths diverge more strongly than light beams with smaller wavelengths, all else being equal.

As a result, smaller-wavelength beams can be made much narrower than larger-wavelength beams. The narrowness of a light beam therefore is ultimately limited by wave diffraction, which depends on wavelength, and not by a physical width of photon particles. The way to get the narrowest beam of light possible is by using the smallest wavelength available to you and focusing the beam, and not by lining up photons which doesn't really make sense in the first place. Improve this answer.

Time4Tea Time4Tea 3, 1 1 gold badge 16 16 silver badges 41 41 bronze badges. They might show it in sci-fi movies, but that's not real. Normally, you won't even be able to see a laser beam in air, unless there are dust particles present.

I "knew" that wasn't how lasers worked from watching G. Joe cartoons. So if you have a beam that is red and blue, and it travels through a medium that predominantly scatters blue, when the beam hits a diffuse surface, it will appear red dish , while the beam itself in flight might appear blue ish.

However, note that laser light is monochromatic - so both the beam visible if there's enough scattering and the right light conditions and the spot it hits will be the same color. Red, on the other hand, needs to be either very powerful or use a different mode of scattering - most commonly, fog, dust, that kind of stuff.

Show 11 more comments. Sign up or log in Sign up using Google. But there would be no light! The room and everything in it would look black. The appearance of black is merely a sign of the absence of light. When a room full of objects or a table, a shirt or a sky looks black, then the objects are not generating nor reflecting light to your eyes. And without light, there would be no sight. The objects that we see can be placed into one of two categories: luminous objects and illuminated objects.

Luminous objects are objects that generate their own light. Illuminated objects are objects that are capable of reflecting light to our eyes. The sun is an example of a luminous object, while the moon is an illuminated object. During the day, the sun generates sufficient light to illuminate objects on Earth. The blue skies, the white clouds, the green grass, the colored leaves of fall, the neighbor's house, and the car approaching the intersection are all seen as a result of light from the sun the luminous object reflecting off the illuminated objects and traveling to our eyes.

Without the light from the luminous objects, these illuminated objects would not be seen. During the evening when the Earth has rotated to a position where the light from the sun can no longer reach our part of the Earth due to its inability to bend around the spherical shape of the Earth , objects on Earth appear black or at least so dark that we could say they are nearly black.