Level Up Answers
Level 0
Circuit A: Req=R1+R2+R3=9Ω
Circuit B: Ceq=(1C1+1C2+1C3)−1=2.3mF
Circuit C: Ceq=C1+C2+C3=21mF
Circuit D: Req=(1R1+1R2+1R3)−1=0.92Ω
Level 1
Circuit A: Req=350Ω
Circuit B: Req=400Ω
Circuit C: Ceq=235μF
Circuit D: Ceq=176.25μF
Level 2
Circuit A:
Circuit B:
Circuit C
Circuit D
Level 3
Circuit A
Circuit B
Circuit C
Circuit D
Level 4
Circuit A
Given:
V1=9V, V2=6V, R=100Ω
Simplify Circuit:
- R1 and R2 in series, R1+R2=200Ω
Node Rule:
- I1+I2=I3
Loop Rule:
- Loop A: V1−I1R12−I3R3=0
- Loop B: I3R3−I2R4−V2=0
- Loop C: V1−I1R12−I2R4−V2=0
Solution:
I1=0.024A, I2=0.018A, I3=0.042A
*note can use wolfram/online/calc to evaluate I from loop AND node rule equations
Circuit B
Given:
V1=9V, V2=6V, R=100Ω
Simplify Circuit:
- R1 || R2, R12=50Ω
Node Rule:
- I1=I2+I3
Loop Rule:
- Loop A: V1−I1R12−I3R3=0
- Loop B: V2−I2R4+I3R3=0
- Loop C: V1−I1R12−V2−I2R4=0
Solution:
I1=0.12A, I2=0.09A, I3=0.03A
Circuit C
Given:
V1=9V,V2=6V,R=100Ω
Simplify Circuit:
- R2 and R3 in series, R2+R3=200Ω
- R4 || R5, R12=50Ω
Node Rule:
- I1=I2+I3
Loop Rule:
- Loop A: V1−I1R1+V2−I1R45=0
- Loop B: −V2−I3R23=0
- Loop C: V1−I1R1−I3R23−I1R45=0
Solution:
I1=0.06A, I2=0.09A, I3=−0.03A
Circuit D
Given:
V1=9V,V2=6V,R=100Ω
Simplify Circuit:
- R2 and R3 in series, R2+R3=200Ω
- R1||R23, R12=66.667Ω
Node Rule:
- I1=I2+I3
Loop Rule:
- Loop A: V1−I1R123−0
- Loop B: I2R123−V2−I3R4=0
- Loop C: V1−V2−I3R4=0
Solution:
I1=0.165A, I2=0.135A, I3=0.03A
Level Bonus
a) Initially there is current in all branches of the circuit (uncharged capacitors act like wires - current can pass through).
b) Ii=0.00436A
d) Current goes through all branches without a capacitor (charge capacitors act like a break in the circuit - no current)
e) If=0.0036A
f) If the switch is opened, the capacitors would discharge through the resistors below.