
EMFan ann an sreath agus co-shìnte
Ma tha dà no barrachd thùsan dealan-motair (emf) ceangailte mar a chithear san fhigear, tha an emf air a chur ann an sreath.
An co-ionann bholtaids Is e an stòr (ε):
ε = ε1 + ε2 + εn
Is e an aghaidh a-staigh co-ionann (r):
r = r1 +r2 +rn
Is e an sruth dealain a tha a’ sruthadh tron aghaidh taobh a-muigh (R):
Mise = ε / (r + R)
Eisimpleir de dhuilgheadas:
Ma tha dà bataraidh a’ cleachdadh emf de 1.5 Volt agus gu bheil an aghaidh a-staigh anns gach bataraidh 0.1 Ω. Tha an aghaidh a-muigh (R) = 10 Ω. Stiùireadh an t-sruth dealain deiseal.
Cleachd am foirmle roimhe:
ε = 1.5 + 1.5 = 3 Volt
r = 0.1 + 0.1 = 0.2 Ω
I = ε / (r + R) = 3 / (0.2 + 10)
I = 3 / 10.2
I = 0.294 A
Cleachd an dàrna riaghailt aig Kirchhoff:
1.5 – 0.1 I + 1.5 – 0.1 I – 10 I = 0
3 – 0.2 I – 10 I = 0
3 – 10.2 I = 0
3 = 10.2 I
I = 3 / 10.2
I = 0.294 A
Ma tha dà no barrachd stòran dealan-motair (emf) ceangailte mar a chithear san fhigear, tha an emf ceangailte ann am parail.
Is e an stòr bholtaids co-ionann (ε):
ε = ε1 = tha2 = than
Is e an aghaidh a-staigh co-ionann (r):
1/r = 1/r1 + 1/r2 + 1/rn
Is e an sruth dealain a tha a’ sruthadh tron aghaidh taobh a-muigh (R):
Mise = ε / (r + R)
Eisimpleir de dhuilgheadas:
Ma tha dà bataraidh a’ tomhas le emf de 1.5 Volt agus gu bheil luach an aghaidh anns gach bataraidh 0.1 Ω. Tha an aghaidh taobh a-muigh (R) = 10 Ω.
Cleachd am foirmle roimhe:
ε = 1.5 Volt
1/r = 1/0.1 + 1/0.1 = 2 / 0.1
r = 0.1 / 2 = 0.05 Ω
I = ε / (r + R) = 1.5 / (0.05 + 10) = 1.5 / 10.05
I = 0.149 A
Cleachd riaghailt Kirchhoff
Cuir a-steach Kirchhoffa’ chiad riaghailt:
I1 + I.2 = Mise ………. Co-aontar 1
Dèan mion-sgrùdadh air lùb Aefca. Tha stiùireadh a’ lùb deiseal. Cuir an dàrna riaghailt aig Kirchhoff an sàs:
ε2 - I.1 r2 – IR = 0
1.5 – 0.1 I1 – 10 I = 0
– 0.1 I1 = 10 I – 1.5
I1 = (10 I – 1.5) / – 0.1
I1 = -100 I + 15 ………. Co-aontar 2
Dèan mion-sgrùdadh air lùb Befdb. Tha stiùireadh na lùibe deiseal. Cuir an dàrna lagh aig Kirchhoff an sàs:
ε1 - I.2 r1 – IR = 0
1.5 – 0.1 I2 – 10 I = 0
- 0.1 I2 = 10 I – 1.5
I2 = (10 I – 1.5) / – 0.1
I2 = -100 I + 15 ………. Co-aontar 3
Cuir co-aontaran 2 agus 3 an àite co-aontar 1:
I1 + I.2 = Mise
-100 I + 15 – 100 I + 15 = I
– 200 I + 30 = I
30 = I + 200 I
30 = 201 I
I = 30 / 201
I = 0.149 A
Cuir às do cho-aontar 2 agus 3:
I1 = -100 I + 15
I2 = -100 I + 15
———————– –
I1 - I.2 = 0
I1 = Mise2 ………. Co-aontar 4
Seach gu bheil mi1 + I.2 = Mise, far a bheil mi1 = Mise2 an uairsin mi1 = Mise2 = 1/2 I = 1/2 (0.149) = 0.0745 A.