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10 Interesting Facts About Light Waves

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waves of light

Light is vital to our existence, and it travels via energy waves called light waves. These waves are not only important because they enable us to see, but we use different types of light, which include radio and microwaves, for a vast range of different purposes. Below are 10 interesting facts about light waves.

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Top 10 Light Wave Facts:

1. Light Is a Type of Radiation

Radiation is a type of energy that travels as electromagnetic waves. Visible light is a form of radiation. It travels in waves, with wavelength being the distance between two waves, measured at the peaks. Wavelength is actually what determines the color of light that we see, with red light having twice the wavelength of blue light, which has a wavelength of a third of one-millionth of a meter. Frequency is the number of waves that occur within a second.

light painting made through long shutter speed

Image Credit: Jan Huber, Unsplash


2. Radio Waves Are Actually a Type of Light Wave

When we think about light waves, we typically think of visible light, which is the only type of light that humans can see. However, there are many other types of light waves, including X-rays, gamma rays, microwaves, and even radio waves. Although some people mistakenly think of radio waves as being related to sound because we listen to audio on radios, it is a form of light wave with a wavelength that is billions of times longer than visible light.


3. Light Waves Travel in a Straight Line

Light waves only travel in a straight line. When light waves hit an opaque object, they are effectively stopped and shadows form where light waves are prevented by solid objects. Light waves can, however, be reflected, refracted, and diffracted.

Reflection means that the waves change direction as they bounce off a barrier. Waves refract when they move from one medium to another. And they also diffract, which means that they can essentially bend around corners.

young man with flashlight

Image Credit: Andreas Dress, Unsplash


4. Light Waves Travel Poorly Through Water

Light waves travel different distances through different types of medium. Light can, theoretically, travel forever in space but travels shorter distances in air and even shorter in water. Most visible light is absorbed by the ocean by the time you reach a depth of around 10 meters, and it is pitch black by the time you reach a depth of 100 meters.


5. Light Is a Form of Energy Consisting of Electric and Magnetic Fields

Light is a type of electromagnetic wave, which means that it consists of both electric and magnetic fields. Other types of electromagnetic waves include radio waves, microwaves, infrared, ultraviolet, X-rays, and gamma rays. While visible light is the only type that can be seen with the naked eye, there are various sensors and other methods that can be used to detect and even “view” other forms of electromagnetism. 


6. Light Wavelengths Are Billionths of a Meter Long

Wavelength is the distance between the peak of one wave and the next. Visible light has a wavelength between 400–700 billionths of a meter long. We see light with the longest wavelengths as the color red and light with the shortest wavelength as violet. The rainbow is actually made up of light waves with millions of different wavelengths, but we can only differentiate between the seven colors.

green laser light

Image Credit: Juergen Faelchle, Shutterstock


7. Visible Light Waves Are the Only Light Waves We Can See

Visible light is the only type of electromagnetic wave that we can see with the naked eye, but we can use UV detectors to view this type of wave. Some animals can also see UV light. X-rays are also viewed using a detector, which then projects the X-rays onto a screen for us to be able to see. 


8. White Light Is Made Up of Every Other Color of the Visible Light Spectrum

White light is, in fact, made up of every other color in the spectrum: red, orange, yellow, green, blue, indigo, and violet. This means that, while other colors can be assigned a wavelength, white light can only be given a broad wavelength range between 400–700 billionths of a meter.


9. Light Waves Can Travel Through a Vacuum

Light waves are capable of traveling through different mediums. They can travel through the air and water, although not very far through the latter. They can also travel through a vacuum, unlike sound, which is why we can see the light of the sun.

Sunlight

Image By: Pixabay


10. Light Waves Can Travel at Nearly 300,000 Kilometers Per Second

Light waves travel faster than any other waves, at least in a vacuum. They travel at approximately 300,000 kilometers per second, which is described as the speed of light—nothing else can travel at this speed. Because nothing can travel faster than this, it means that humans are unlikely to be able to ever travel beyond the confines of the Milky Way

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Conclusion

Light waves are a form of electromagnetic waves, like X-rays and infrared, although visible light is the only type of light wave that humans can see with the naked eye. They travel in straight lines, can travel through a variety of mediums including a vacuum, and can reach a speed of nearly 300,000 kilometers per second in a vacuum.


Featured Image Credit: Clyde He, Unsplash

About the Author Robert Sparks

Robert’s obsession with all things optical started early in life, when his optician father would bring home prototypes for Robert to play with. Nowadays, Robert is dedicated to helping others find the right optics for their needs. His hobbies include astronomy, astrophysics, and model building. Originally from Newark, NJ, he resides in Santa Fe, New Mexico, where the nighttime skies are filled with glittering stars.

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