Origin: From Latin trans- (across/through) and mittere (to send).
Modern Meaning: When energy or light passes all the way through a material.
Think of a "transmitter" radio or a "transmission" in a car—it's all about moving energy from one side to the other!
Transmission happens when a material's atoms do not absorb the light's energy. Instead of being soaked up (absorption) or bouncing back (reflection), the light waves travel through the gaps between the atoms and come out the other side.
Clear glass or pure water allow complete transmission. Light passes through with almost no change, letting you see clearly.
Frosted glass or wax paper allow partial transmission. Light gets through, but it gets scattered (spread out) so you can't see sharp images.
Mind-Blowing Fact: X-rays are a form of high-energy light that can transmit through your skin and muscles, but get absorbed by your bones. That's how doctors "see" your skeleton!
The internet you are using right now works because of transmission! Most high-speed data travels through fiber-optic cables.
These cables are made of incredibly thin strands of glass, as thin as a human hair. Instead of electricity, they use light to carry information. Because the glass is so pure, it allows for nearly perfect transmission of light pulses over huge distances.
Engineers design these cables so the light stays trapped inside the glass, bouncing along the edges but always transmitting forward. This allows movies, games, and video calls to travel across the ocean in a fraction of a second!