Odd capacitor questions

[Danijel Gorupec]

Hi,

 

If you have a simple capacitor made of two identical metal plates. After you put a charge on it...

 

1. does the negative plate becomes any heavier (greater mass) than the positive one? (For the difference in number of electrons inside. Or am I missing some other effects.)

 

2. does the negative plate becomes any warmer (higher temperature) than the positive one? (Because I imagine electrons as a 'gas' inside metal -> 'pressure' is reduced on the positive plate, and increased on the negative.)

 

Thanks.

[swansont]

Hi,

 

If you have a simple capacitor made of two identical metal plates. After you put a charge on it...

 

1. does the negative plate becomes any heavier (greater mass) than the positive one? (For the difference in number of electrons inside. Or am I missing some other effects.)

 

2. does the negative plate becomes any warmer (higher temperature) than the positive one? (Because I imagine electrons as a 'gas' inside metal -> 'pressure' is reduced on the positive plate, and increased on the negative.)

 

Thanks.

 

 

1. Yes, though this is a small amount. The positive side will have lost some electrons, and the negative side will have gained them.

 

2. There will be some resistive heating as the capacitor charges. I'm not sure of any other effects, and after it is charged the system will tend to cool to ambient temperature.

[Danijel Gorupec]

Thanks Swansont. I am aware of resistive heating. Still I was thinking if there is any temperature effect from 'stuffing more electrons inside' - as it would be when you stuff more gas into a container (adiabatic heating).

[emrekanca]

It reminds me of a cool stuff called peltier.

http://www.wordiq.com/definition/Peltier_effect

I dont understand how it works but maybe the same event can occure in capacitor.

Because there is electron movment,loss,gain

Also the same event can happen without semiconductors.