series capacitor values..

[smithie]

hi
can someone tell me what the total value of these caps in series would add up to as i dont know the formular.
at presant i have two 47pf in series and that equals 23.5pf,so i understand that bit,but ive now added another 47pf in series so am unsure what total value i have now?
im also thinking of adding 4 47pf in series so any ideas what that total value will be?
im just using the parts i have laying around and experimenting with a feedback circuit on my amp,i just need to know these values to give me a idea what values to order when the time comes for decent stuff.
any help much appricated.
all the best
smithie

 

[Frank Berry]

47pf divided by three is 15.67p.
47pf divided by four is 11.75pf.

 

[Eli Duttman]

Equal value caps. in series is easy. Just divide by the number of parts.

Caps. in series follow a reciprocal Law, just like resistors in parallel.

1/C_net = 1/C₁ + 1/C₂ + 1/C₃ + ... + 1/C_n

 

[smithie]

hi guys
thank you so much,youve been a great help and ive now made a note of the formular.
once again much appricated
all the best
smithie