Do you think cell phones pose a health risk?

AI Thread Summary
Microwave ovens and cell phones operate on similar frequency ranges, but microwaves use significantly more power, typically around 500W compared to a maximum of 2W for cell phones. This power difference explains why microwaves can cook food while cell phones cannot. A demonstration involving multiple cell phones stacked on an egg failed to cook it, as the energy from the phones disperses in all directions, providing minimal heating effect. There is no credible evidence suggesting that cell phones pose a health risk, and other devices like cell phone jammers and Wi-Fi emit much less radiation than cell phones. Overall, the consensus is that cell phones do not pose a significant health threat.
localrob
Messages
23
Reaction score
1
I have a few questions/thoughts about microwaves ovens and cell phones that I'm hoping someone here can help with.
Microwaves ovens and cell phones both use around the same range of frequencies. But microwave ovens use way more power. Ovens about 500W, cell phones at most 2W. More power would result in higher intensity for a given area. This is why an oven cooks food and cell phones don't. Correct me if I'm wrong.

I saw a program on tv where they piled a bunch of cell phone on an egg and called them to see if they would cook the egg. It didn't, but they didn't explain why.
Can blasting an egg with a low power frequency ever equal a high power frequency?
I know that the photoelectric effect says blasting it with lower frequency photons won't be the same as one high powered photon.

And some final questions. Do you think cell phones pose a health risk? What about a cell phone jammer that is blasting out multiple frequencies all the time? What about wifi signals that are all around us?
 
Physics news on Phys.org


What do you think would happen to a cell phone if placed in a 500W oven? I'm pretty sure a pile of cellphones would produce enough power to start damaging each other before significantly heating the egg.

And just how many cell phones did they have? Even with 20 cell phones you are not getting a 10th of the power of a small microwave oven.
 


localrob said:
I have a few questions/thoughts about microwaves ovens and cell phones that I'm hoping someone here can help with.
Microwaves ovens and cell phones both use around the same range of frequencies. But microwave ovens use way more power. Ovens about 500W, cell phones at most 2W. More power would result in higher intensity for a given area. This is why an oven cooks food and cell phones don't. Correct me if I'm wrong.
Residential ovens are typically 1200 or 1500W. Cell phone power output is variable - it only outputs 2W if the nearest cell tower is having a tough time connecting.
I saw a program on tv where they piled a bunch of cell phone on an egg and called them to see if they would cook the egg. It didn't, but they didn't explain why.
Assuming all the phones were putting out their peak power, it would take 600 of them to produce the same power as a typical small microwave.

But the main problem with this approach is that a microwave oven is closed, which makes all of that 1200 watts go into the egg. A pile of cell phones still emits its energy in all directions, so that egg is only going to get a tiny fraction of that energy - probably not even 1%.
Can blasting an egg with a low power frequency ever equal a high power frequency?
I know that the photoelectric effect says blasting it with lower frequency photons won't be the same as one high powered photon.
Microwaves interact with water, which causes it to heat up. It doesn't interact the same way with other materials. Different frequencies of radiation will have different interactions with different materials.
And some final questions. Do you think cell phones pose a health risk?
No: There is no credible study showing an apparent risk or any mechanism theoriezed for how they could cause damage.
What about a cell phone jammer that is blasting out multiple frequencies all the time? What about wifi signals that are all around us?
Unless you wear them as a hat, they send substantially less radiation through your head than a cell phone does, so no.
 
Thread 'Gauss' law seems to imply instantaneous electric field propagation'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Maxwell’s equations imply the following wave equation for the electric field $$\nabla^2\mathbf{E}-\frac{1}{c^2}\frac{\partial^2\mathbf{E}}{\partial t^2} = \frac{1}{\varepsilon_0}\nabla\rho+\mu_0\frac{\partial\mathbf J}{\partial t}.\tag{1}$$ I wonder if eqn.##(1)## can be split into the following transverse part $$\nabla^2\mathbf{E}_T-\frac{1}{c^2}\frac{\partial^2\mathbf{E}_T}{\partial t^2} = \mu_0\frac{\partial\mathbf{J}_T}{\partial t}\tag{2}$$ and longitudinal part...
Thread 'Recovering Hamilton's Equations from Poisson brackets'
The issue : Let me start by copying and pasting the relevant passage from the text, thanks to modern day methods of computing. The trouble is, in equation (4.79), it completely ignores the partial derivative of ##q_i## with respect to time, i.e. it puts ##\partial q_i/\partial t=0##. But ##q_i## is a dynamical variable of ##t##, or ##q_i(t)##. In the derivation of Hamilton's equations from the Hamiltonian, viz. ##H = p_i \dot q_i-L##, nowhere did we assume that ##\partial q_i/\partial...
Back
Top