D.C. Circuits

🚗 S e c 4 N A C o m b in e d P h y s ic s S h a r e D o c u m e n t S t y le D . C . C i r c u i t s A d d S o u rc e Ta g RE C A P W h a t i s S er i es a n d P a r a l l el C i r c u i t s ? S er i es C i r c u i t s In a s e r ie s c irc u it , t h e c o m p o n e n ts a re c o n n e c te d o n e a f t er a n o t h er in a s in g le lo o p ; t h e re is o n ly o n e p a t h t h ro u g h w h ic h el ec t r i c c u r r en t c a n f lo w. 2/22/25, 10:38 AM D.C. Circuits https://www.remnote.com/w/63c4983acdbac42fbe812c31/DC-Circuits-iF21pXVd3xI06cokl 1/8

If a re s is to r is a d d e d to t h e c irc u it , t h e c u r re n t w ill d e c re a s e a s a re s is to r r es i s t s . T h e a m m e te r w i l l n o t a f fe c t t h e c irc u it , it o n ly m e a s u re s t h e c u r re n t in A m p e re A , h e n c e , t h e y w ill g iv e t h e s a m e c u r re n t re a d in g . In a s e r ie s c irc u it , t h e c u r re n t w ill b e t h e s a m e . In a s e r ie s c irc u it , t h e e f fe c t iv e re s is t a n c e is a lw a y s g r ea t er t h a n t h e la rg e s t o f t h e in d iv id u a l re s is t a n c e s . O h m ' s l a w V IR W h e re : V Vo lt a g e I C u r re n t R R e s is t a n c e ( Ω ) P o t en t i a l D i f f er en c e i n a S er i es C i r c u i t 2/22/25, 10:38 AM D.C. Circuits https://www.remnote.com/w/63c4983acdbac42fbe812c31/DC-Circuits-iF21pXVd3xI06cokl 2/8

S I U n it o f e .m .f a n d v o lt a g e is Vo lt V RE C A P R es i s t a n c e o f d i f f er en t a p p a r a t u s es Vo lt m e te r In f in ite re s is t a n c e A m m e te r Ve r y n e g lig ib le re s is t a n c e t h a t w e a s s u m e it to b e z e ro in a n id e a l s it u a t io n , t h e p o te n t ia l d if fe re n c e a c ro s s t h e w h o le c irc u it is e q u a l to t h e e .m .f. o f t h e e le c t r ic a l s o u rc e . T h is is b a s e d o n t h e P r in c ip le o f C o n s e r v a t io n o f E n e rg y ; c h e m ic a l p o te n t ia l e n e rg y f ro m t h e s o u rc e is c o n v e r te d to h e a t in t h e t w o re s is to r s .) In re a lit y, t h e e .m .f. o f t h e e le c t r ic a l s o u rc e is n o t e q u a l to t h e p .d . a c ro s s t h e w h o le c irc u it . T h e p .d . a c ro s s t h e c irc u it w ill b e lo w e r t h a n t h e e .m .f. o f t h e e le c t r ic a l s o u rc e . T h is is b e c a u s e t h e e le c t r ic a l s o u rc e h a s in te r n a l re s is t a n c e . E x a m p l e q u es t i o n r 1 1 o h m r 2 5 o h m s 2/22/25, 10:38 AM D.C. Circuits https://www.remnote.com/w/63c4983acdbac42fbe812c31/DC-Circuits-iF21pXVd3xI06cokl 3/8

r 3 1 0 o h m s r 4 2 o h m s To t a l re s is t a n c e 1 8 o h m s R e s is to r w it h t h e m o s t re s is t a n c e 1 0 A d d t a b le h e re ) P a r a l l el C i r c u i t s V IR V P o te n t ia l D if fe re n c e ) b e t w e e n p o in ts X a n d Y is c o n s t a n t I1 is p a s s in g t h ro u g h R 1 a n d I2 is p a s s in g