Physics
Mr. Tothero
Name: ________________________
Period: _____
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 30Ω. 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).
10Ω
Ω
15Ω
Ω
9V
20Ω
Ω
30Ω
Ω
25Ω
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
15Ω
Ω
30Ω
Ω
45Ω
Ω
Req: ________________________
60Ω
Ieq: ________________________
Req = R1 + R2 +
(Series)
1
1
1
= + +
Req R1 R2
(Parallel) R =
V
(Ohm’s Law)
I
10. A 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).
44Ω
Ω
60Ω
24V
20Ω
Ω
80Ω
Ω
Req: ________________________
Ieq: ________________________
Req = R1 + R2 +
(Series)
1
1
1
= + +
Req R1 R2
(Parallel) R =
V
(Ohm’s Law)
I
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).
15Ω
Ω
60Ω
Ω
43Ω
13V
33Ω
Ω
200Ω
Ω
99Ω
45.25Ω
Ω
Req: ________________________
Ieq: ________________________