When Do You Know When to Change Ac Filter
Have you ever wondered if your microwave oven leaks radiation? If and so, it turns out there is a pretty simple test to cheque the radiation seal on your microwave oven.
But, earlier nosotros get into that, let'south find out what exactly goes on within one.
How does a microwave cook food?
Take you ever wondered how that magical metal box in your kitchen heats up food and drinks? As it turns out, the process of "cooking" foods in a microwave oven is really pretty interesting.
The secret comes from the namesake of the machine — microwaves. In instance yous unaware, these are a type of electromagnetic radiation (like light and radio waves) that lie towards the longer wavelength of the EM spectrum.
Microwaves have frequencies ranging from about 1 billion cycles per second (one GHz) upwardly to 300 times that and have wavelengths (the altitude between peaks) of between 12 inches (30 cm) and 0.04 inches (1 mm). To put that into perspective, radio waves typically have wavelengths varying from 1 mm to 100 km, and the light visible to our human being eyes roughly falls betwixt 380 to 700 nanometers (a sail of newspaper is typically100,000 nanometers thick).
Inside a microwave oven, microwaves are generated in a piece of tech chosen a magnetron and are beamed into the metal interior of the microwave oven. Here, anything you lot put inside the microwave oven (food or drinkable, etc) absorbs these rays.
These microwaves excite the water molecules within the food/drink, causing information technology to heat upwards rapidly. The higher the water content within the target food/beverage, the faster they tend to melt, so that moist items cook a lot faster than more desiccated items.
For bigger chunks of food, the microwaves actually only cook the outermost layers of the nutrient, with the inner bits cooked via conduction of heat from the exterior in.
With all that radiations shooting around inside the microwave oven, information technology is patently not ideal to have much of it leaking outside the box. For this reason, devices similar microwave ovens must go through rigorous testing earlier they can exist released for general utilize.
How do your test your microwave for radiation leakage?
While very high standards are typically fix for the tolerable levels of microwave leakage from microwave ovens, some microwaves can, and inevitably will escape. So, how do you test how effective the microwave shielding is on your microwave?
As it turns out, there is really quite a simple test.
A fascinating, if non slightly disconcerting video by Physics Daughter shows united states why nosotros should probably all check our microwave ovens. Her simple experiment shows us that there is an easy and effective manner to check the integrity of the radiation shielding on your kitchen appliance.
And all it takes is a little flake of lateral thinking.
Microwave ovens, like prison cell phones, emit radiations in a specific ring of EM frequencies -- specifically radio waves. All things being equal, you should expect that by placing your telephone inside a microwave and closing the door the signal would be blocked past the shell of the microwave oven.
If this is the case, it would also be reasonable to assume that you shouldn't be able to ring the telephone in one case information technology is safely locked within.
Information technology turns out, this is non actually the example. Somehow, and somewhere, EM radiations is able to achieve the telephone's antennae, resulting in you lot being able to phone call information technology from outside!
Only how?
As it turns out, the main form of shielding built into the microwave is a device chosen a "Faraday cage". These types of devices piece of work dissipating the charge from EM radiation around their structure. This happens because electrons in the metallic are excited by the radiation and move throughout the metallic construction of the cage, creating an electric field that opposes and cancels out the external wave or field of anything inside it.
In this sense, Faraday cages are effectively hollow conductors. Any breach in the structure of this cage can, theoretically, permit minor amounts of EM radiation to "leak" within (or exterior) of the cage.
According to this experiment, it appears this is indeed the case for some microwave ovens.
Do all microwave ovens leak radiation?
This simple experiment is interesting, merely information technology is non possible to quantify exactly how much leakage your microwave oven may accept. For this reason, more sophisticated ways of investigation are required.
For example, are all microwave ovens equal? Perchance yours is of a lower quality than others?
If you were to echo the experiment using different ovens, as Physics Girl did, you will probable discover that some do block the cellphones, while others practice not.
Edifice on her findings, she decided to detect which office of the microwave was actually letting the radiation escape. Using aluminum foil to act as a near-perfect Faraday cage, she completely wrapped her phone. Certain plenty, no one was able to telephone call her phone.
The adjacent step was to wrap certain parts of the microwave oven to narrow down and seek out the "leaky" parts. By systematically leaving parts of the microwave unwrapped they hoped to find the leak. It turned out that the door was the near likely culprit.
What are some other simple tests for microwave radiation leaks?
To confirm her theory, Physics Girl employed the services of a self-professed hacker to make use of a HackRF radio transmitter and receiver to conduct a more sophisticated experiment. These devices can receive and transmit signals from 1 MHz to 6 GHz.
Using the device and a bona fide Faraday cage, they were able to demonstrate that you shouldn't be able to call a phone shielded by one — if it is fully intact.
Next, they tested whether commonly used Wi-Fi signals tin go through the microwave'due south door. Wi-Fi signals utilize a like frequency to microwave ovens then this is an interesting examination. Microwaves typically operate at around 2.45 Gigahertz, whilst cellular signals tend to be around 1.9 Gigahertz or 850 megahertz.
Sure enough, they were able to FaceTime the telephone through the microwave door.
Interestingly, older microwave ovens have been shown to impact the quality of your domestic Wi-Fi routers and devices! Merely, we digress.
Using the aforementioned detector they were also able to directly observe microwave energy outside of the microwave oven too.
They hypothesized that the radiation could be exploiting holes in the shielding of the door, allowing the microwave oven to leak radiation. Every bit Physics Girl points out, her experiments show that some microwaves practice let the specific frequencies of mobile phones through, providing articulate evidence that some form of radiation leakage is possible inside these appliances.
Physics Daughter does notation that their experiment had a very pocket-size sample size, did not take into consideration the microwave oven's age or its proximity to a cellular tower.
These variables could bear on the results.
Should you exist worried if you find that your microwave is leaking?
FDA regulations really allow for a small amount of leakage over the lifetime of the microwave, of nearly 5 mW/cm2at approximately 2 inches (5 cm) from the oven surface. The radiation itself is non-ionizing so won't damage your Dna directly, rather information technology volition excite the water within your soft tissues.
The FDA does warn that high exposure to microwaves can lead to a painful burn. Organs like eyes and testes are particularly vulnerable considering they have relatively little blood flow to behave away the heat. Also, the lens of the human eye is very sensitive to heat. Loftier levels of microwaves could cause cataracts.
The FDA as well notes that this kind of damage would require a big corporeality of radiations.
And then, should y'all be concerned if your microwave oven leaks radiation? Put just, no.
You are more likely to injure yourself from a heated drinking glass of water than the radiation itself. The radiations will not exist in a high enough dose to cause y'all any impairment.
And then, fifty-fifty if you find that your microwave leaks some radiation, it is of such a pocket-sized amount and a non-mutagenic kind, that shouldn't really lose sleep over it. Though, standing very close to your microwave at all times when information technology is in functioning should probably be avoided.
Source: https://interestingengineering.com/this-simple-test-lets-you-know-if-your-microwave-has-a-radiation-leak
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