I really can’t grasp the concept of waves. I can imagine it a bit for sound waves: a speaker has a surface that pushes air, and the moving air eventually pushes the membrane in our ears.
But I’m confused about wifi etc. What exactly is the thing that physically travels? Is it air or something else? Does it physically move in a wavy pattern?
Edit: thanks for all the answers! But damn I’m overwhelmed. It’s gonna take me days to read and fully understand the answers. But thanks!
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On the electromagnetic spectrum, you have radio waves on one end, gamma rays on the other end. In the middle, there’s a narrow band of visible light, following the colors of the rainbow. 🌈
So on the lower energy end of this spectrum you have radio waves which can be emitted at a specific frequency and received.
It was thought that some sort of medium was needed to transmit such waves, this lead to the mistaken belief of the “luminiferous ether.” But emissions of the electromagnetic spectrum do not require any media to carry it. It is a form of radiation.
Visible light and radiant heat are two kinds of electromagnetic waves humans have always been able to sense. But there are other electromagnetic waves we cannot see or feel and only discovered in the industrial age, and radio waves are one of them. So are gamma rays, x-rays, and microwaves.
You can think of an electromagnetic waves as a stream of photons, with each photon a quantum of energy. A photon sometimes acts like a particle and sometimes acts like a wave. The photon is a fundamental particle — that is, it’s not made up of other particles. But it has no mass. What photons do have is a frequency, and that determines where it belongs on the electromagnetic spectrum. Even if it’s not in the visible spectrum, it moves at the speed of light.
If you are having trouble visualizing a photon, you aren’t alone. Quantum mechanics is not intuitive at all, and even the physicists who understand the math and win Nobel Prizes admit as much. Nobel Prize winner Richard Feynman famously said “I think I can safely say that nobody understands quantum mechanics.” And if he didn’t understand it, what chance does the ordinary non-physicist have? But we do know it works, and we can use it in all kinds of ways, including wi-fi and radio.
Visible light and radiant heat are two kinds of electromagnetic waves humans have always been able to sense. But there are other electromagnetic waves we cannot see or feel and only discovered in the industrial age, and radio waves are one of them. So are gamma rays, x-rays, and microwaves.
You can think of an electromagnetic waves as a stream of photons, with each photon a quantum of energy. A photon sometimes acts like a particle and sometimes acts like a wave. The photon is a fundamental particle — that is, it’s not made up of other particles. But it has no mass. What photons do have is a frequency, and that determines where it belongs on the electromagnetic spectrum. Even if it’s not in the visible spectrum, it moves at the speed of light.
If you are having trouble visualizing a photon, you aren’t alone. Quantum mechanics is not intuitive at all, and even the physicists who understand the math and win Nobel Prizes admit as much. Nobel Prize winner Richard Feynman famously said “I think I can safely say that nobody understands quantum mechanics.” And if he didn’t understand it, what chance does the ordinary non-physicist have? But we do know it works, and we can use it in all kinds of ways, including wi-fi and radio.
Visible light and radiant heat are two kinds of electromagnetic waves humans have always been able to sense. But there are other electromagnetic waves we cannot see or feel and only discovered in the industrial age, and radio waves are one of them. So are gamma rays, x-rays, and microwaves.
You can think of an electromagnetic waves as a stream of photons, with each photon a quantum of energy. A photon sometimes acts like a particle and sometimes acts like a wave. The photon is a fundamental particle — that is, it’s not made up of other particles. But it has no mass. What photons do have is a frequency, and that determines where it belongs on the electromagnetic spectrum. Even if it’s not in the visible spectrum, it moves at the speed of light.
If you are having trouble visualizing a photon, you aren’t alone. Quantum mechanics is not intuitive at all, and even the physicists who understand the math and win Nobel Prizes admit as much. Nobel Prize winner Richard Feynman famously said “I think I can safely say that nobody understands quantum mechanics.” And if he didn’t understand it, what chance does the ordinary non-physicist have? But we do know it works, and we can use it in all kinds of ways, including wi-fi and radio.
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