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Questions tagged [microwaves]

Microwaves, broadly defined, are electromagnetic radiation with wavelengths ranging from one meter to one millimeter; or with frequencies between 300 MHz (100 cm) and 300 GHz (0.1 cm). This range includes both UHF and EHF (millimeter waves) and the entire SHF band (3 to 30 GHz, or 10 to 1 cm).

Microwaves, broadly defined, are electromagnetic radiation with wavelengths ranging from one meter to one millimeter; or with frequencies between 300 MHz (100 cm) and 300 GHz (0.1 cm). This range includes both UHF and EHF (millimeter waves) and the entire SHF band (3 to 30 GHz, or 10 to 1 cm).

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Why do metal objects in microwaves spark?

I heard that electrons accumulate at points on metals, and this clearly explains the arcing phenomenon, but how does a microwave make an electron imbalance on the fork?
user24082
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Microwave oven and heating my sons milk

I heat up my sons milk in the microwave... I use the same volume all the time and always punch in 42 seconds (on high) and his milk comes out the perfect temp every time. However, sometimes he wants "mo milk" and I just want to give him a half…
cktech
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Why standing wave is needed in microwave oven?

In microwave oven, standing wave is created in chamber by reflecting from metal surface. Do we create it intentionally? Is there any special advantages of it?
Prerna
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Physics of variable settings on microwave ovens

I've been learning how microwave ovens work and haven't been able to find any information on the practical way manufacturers create variable power settings. If I understand magnetrons correctly they are only designed to emit one…
Jared Rogers
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How could a microwave launch a cup?

This is something that's puzzled me for years and I'm hoping someone here can offer a theoretical explanation and put my curiosity about it to rest. About 15 years ago in my bachelor days I wasn't so good about putting my dishes away and left a…
bob
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Can a mesh shield keep food cold in a running microwave?

Please forgive my amateur physics knowledge. Say it's Thanksgiving leftover day. You load a plate with turkey, potatoes, cranberry sauce, and salad. Now it's time to heat your food, but oh no! You put the cold foods on your plate before using the…
Jaqenn
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Time Domain Reflectometer

How can I analyze the data time domain reflectometer measurement from this picture?
Ammy
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How to melt sand with microwaves?

Is it possible to melt sand with microwaves? Which frequency should they have? The melting point of the sand is 1.700°C and the mass is not homogeneous: there are a lot of pores and the composition of sand is not homogeneous.
Stefano
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Microwave Faraday cage shielding

After a decade of using a microwave oven in my house I figured out I never cared to connect the grounding cable. So my question is regardless of electrical shock risk, does the Microwave Faraday cage shielding work without a ground connection? I am…
Mandrill
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Microwave waveguide position is not symmetric with respect to the center of the cavity

I am using a Panasonic microwave oven for some experiments. I found that the waveguide is not placed centrally on the side wall. The waveguide flap is closer to the back wall of the cavity than it is to the door of the microwave. The turntable is,…
yds1798
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Why do airbags activate when subjected to microwave energy?

I remember watching a few years ago, a show on YouTube called "Is It A Good Idea To Microwave This?" The presenters regularly placed everyday items in a microwave and observed what happened. Episode 167 - Airbag (YouTube) On one episode, they place…
Eric Hernandez
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Why and how does a microwave cavity confine resonant frequency inside it, not other frequency waves?

In microwave oven, the dimension of the chamber is determined according to 2.45 GHz frequency (or 12.2 cm wavelength). The chamber is made of metal and it should reflect all microwaves. Why does this reflection depend on cavity dimension as well as…
Prerna
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Reflection Coefficient --- propagation over a plane earth

In Section 2.1.2 "Propagation Over a Plane Earth" of [1], the author wrote: The reflection coefficient, $R$, of the ground depends on the angle of incidence, $\theta$, the polarization of the wave, and the ground characteristics; it is given by …
Wei-Cheng Liu
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Magnetron Tube Emit Direction

for a project I am doing research on microwave ovens and their operation. I have researched most of the electronic components but I was wondering about one part, the magnetron tube. I have looked it up several times and I cannot find it anywhere,…
user140052
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Dodging Microwaves

I'm not sure if I'm just being paranoid or not but I'd like some explanation as to whether my fears are justified or not. With a normal microwave oven you can usually end the cycle early by opening the door. However there is no apparent delay…
Aequitas
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