Does a neutral body contain any charge?
I think it is yes. However, they have an even distribution of postive and negative charges, henceforth, cancelling out each other charges. Is it right to explain it this way?
Thanks
ok
Originally posted by skythewood:ok
thanks !
Anyway, does anyone know whether acetate strip is charged positively or negatively after rubbing? I haven't heard of this before. would be good if there are sources to aid me. and may i know how one can discharge a polythene strip? By rubbing it with positively charged rod?(just a suggestion though)
whether it will be charged positively or negatively depends on some table which I do not think is in O level syllabus
Discharging can be done by hitting the strip as well. Don't rub it with a positively charged rod. Because for non conductors, it is the rubbing, the friction, that makes the non-conductors get charged.
Originally posted by eagle:whether it will be charged positively or negatively depends on some table which I do not think is in O level syllabus
Discharging can be done by hitting the strip as well. Don't rub it with a positively charged rod. Because for non conductors, it is the rubbing, the friction, that makes the non-conductors get charged.
Thanks. I have been wondering why isn't static electricity used in household and daily appliances? Is it because it gives too much shocks? My friend suggested that it is not a regular supply of power... But surely you can use some machinery to rub it to generate power all the time?
+++++++
__________
A
B
__________
------------
Say an electron moves between these 2 charged parallel plates from point B to A, I think the strength of the electric field on electron falls. However, I do not know how to explain... I might be wrong in my statement. So do correct me. :)
Originally posted by bonkysleuth:Thanks. I have been wondering why isn't static electricity used in household and daily appliances? Is it because it gives too much shocks? My friend suggested that it is not a regular supply of power... But surely you can use some machinery to rub it to generate power all the time?
+++++++
__________
A
B
__________
------------
Say an electron moves between these 2 charged parallel plates from point B to A, I think the strength of the electric field on electron falls. However, I do not know how to explain... I might be wrong in my statement. So do correct me. :)
I have given away all my physics....but what I can think of is this: Static electricity is caused by rubbing 2 non-conducting material. In that case, for static electricity to build up, you can't have a conducting material in contact with the non-conducting, static electricity inducing materials.
So in other words, it is not practical to wait till it build up, and then discharge one bolt and repeat the cycle. Static electricity is more of a nuisance and a potential hazard in some cases.
Originally posted by bonkysleuth:Thanks. I have been wondering why isn't static electricity used in household and daily appliances? Is it because it gives too much shocks? My friend suggested that it is not a regular supply of power... But surely you can use some machinery to rub it to generate power all the time?
+++++++
__________
A
B
__________
------------
Say an electron moves between these 2 charged parallel plates from point B to A, I think the strength of the electric field on electron falls. However, I do not know how to explain... I might be wrong in my statement. So do correct me. :)
Firstly, rubbing is only for non-conductors. You can't use a non-conductor to transmit electricity, as explained by 16/f/lonely ;)
Secondly, this is the reason why it is called static electricity. It is static! Normal household appliances, it is not static.
Thirdly, generators are already using machinery to generate electricity :D
This is more of about Faraday's Law and Lenz's Law... It doesn't seem any more useful or effective to attempt to create something similar with static electricity (although I dun think it is possible).
Fourth, there are instances where charges are stored up before being used, although it does not use static electricity at all. Example: usage of capacitors in camera flashes
Static electricity, although hazardous and could potentially damage appliances, has its own uses as well. One example would be the gold-leaf electroscope. But I think gold-leaf electroscope is out of O level syllabus