Questions tagged [dielectric]
A dielectric is an insulator that can be polarized by applying an electric field. A common example is the use of a dielectric within a capacitor between the metallic plates to increase the surface charge.
8
questions
19
votes
4
answers
65k
views
How does the tester screwdriver work?
How does the tester screwdriver work? If I put the tester screwdriver inside the "hot wire" of an electrical socket, it lits up if I press my finger against the metal cap on top of the screwdriver. ...
2
votes
2
answers
2k
views
Capacitors: voltage-dependent capacitance?
While playing around with a capacitive power supplies, I observed some very weird behavior when passing a 60Hz sinusoidal current through a 1000V disk ceramic capacitor. The voltage curve was very ...
-2
votes
1
answer
1k
views
I want to build a portable railgun and I'm a complete rookie [closed]
I'd like to enter the world of electronic hobbies by making a railgun, and so far I know that I understand the basics of the device and that I need high amounts of direct current.
However, I am ...
6
votes
1
answer
1k
views
What impact, if any, does the solder mask color have on the electrical and mechanical properties of a PCB
At my place of work, we use soldermask colors as a sort of poke-yoke for manufacturing purposes E.g. Technicians know that green pcb goes with green, blue pcb with blue, etc. This has lead to some ... ...
3
votes
1
answer
606
views
How does selecting a higher permittivity substrate in patch antenna reduce its size?
By selecting a higher permittivity substrate do we reduce the height of the antenna or we reduce the length of the patch antenna? We cannot reduce the length of the antenna as it is dependent on the ...
3
votes
2
answers
3k
views
What dielectric liquids can be used as coolants?
I've seen some interesting videos of people putting their computers in containers with sunflower oil, where they continue to work normal.
Are there any other dielectric liquids that can be used to ...
2
votes
1
answer
4k
views
How do internal capacitor stud finders work?
I don't understand how a non-magnetic object like wood can be detected using a stud finder.
For instance, stud finders find wood from the dielectric constant, but I don't understand the principle.
The ...
1
vote
1
answer
179
views
Why does placing an antenna far from the wood increase the efficiency of the antenna?
I designed a monopole antenna at 868MHz frequency. I placed wood as the surrounding material. I noticed that placing the antenna far from the wood increases the efficiency of the antenna. Can anyone ...