Name: ________________________
Period: _____
Series, Parallel to Combination Circuits Worksheet
Req  R1  R2 
(Series)
1
1 1
  
Req R1 R2
(Parallel) R 
V
(Ohm’s Law)
I
Concept Questions
Instructions: Fill in each blank with the appropriate answer. If explanation is required,
do so thoroughly. See if you can do these without notes.
1. All circuits form a complete ________________________, regardless of purpose.
2. Why are circuits drawn in the form of diagrams with symbols?
________________________________________________________________________
________________________________________________________________________
3. The ________________________ circuit has multiple paths for current to flow.
a. Series
b. Parallel
4. A break in the ________________________ circuit will not result in the entire
stoppage of the circuit.
a. Series
b. Parallel
5. In a ________________________ circuit the voltages add, while the currents are
equal.
a. Series
b. Parallel
6. In a parallel circuit, the voltages are ________________________ while the currents
are ________________________.
a. Added/Equal
b. Equal/Added
7. A circuit has 3 resistors, each with a resistance of 30. The circuit is connected
across a 10V battery. Draw the series and parallel version of each of these below.
Series
Parallel
Req  R1  R2 
(Series)
1
1 1
  
Req R1 R2
(Parallel) R 
V
(Ohm’s Law)
I
Problems
Instructions: Answer each question completely, making sure to show your work and
each circuit transition step, if there are any.
8. A certain circuit is shown below.
a. What type of circuit is it? ________________________
b. Solve for the equivalent resistance (Req) of the circuit.
c. Solve for the current in the entire circuit (Ieq).
10
15
9V
20
30

Req: ________________________
Ieq: ________________________
9. A certain circuit is shown below.
a. What type of circuit is it? ________________________
b. Solve for the equivalent resistance (Req) of the circuit.
c. Solve for the current in the entire circuit (Ieq).
18V
15
30
45
Req: ________________________

Ieq: ________________________
Req  R1  R2 
(Series)
1
1 1
  
Req R1 R2
(Parallel) R 
V
(Ohm’s Law)
I
Resistance Practice Problems
1. Calculate total resistance.
2. For complex circuits, circle “groups” and calculate group resistances before total
resistances.
R1
1
R3
20
R4
20
R1
10
R2
10
R3
3
+ V1
9V
R2
2
+
V1
120V
R1
10
+ V1
6V
R1
5
R2
10
R2
5
R3
20
+ V1
220V
R1
1
R3
10
R3
2
R4
10
R2
1
+ V1
6
R6
1
R4
4
R2
1
R5
2
R1
1
R3
1
R5
1
+ V1
6
R4
1
R6
1
1
1 1
  
Req R1 R2
10. A combination circuit is shown below.
Req  R1  R2 
(Series)
(Parallel) R 
V
(Ohm’s Law)
I
a. Circle all of the series/parallel combinations you see and label them.
b. Solve for the equivalent resistance (Req) of the circuit.
c. Solve for the current in the entire circuit (Ieq).
44

24V
20
80
Req: ________________________
Ieq: ________________________
11. A final combination circuit is shown below.
a. Circle all of the series/parallel combinations you see and label them.
b. Solve for the equivalent resistance (Req) of the circuit.
c. Solve for the current in the entire circuit (Ieq).
15

60
13V
33
200

45.25
Req: ________________________
Ieq: ________________________