# Direct Current (D.C) Circuit

**English**

**Natural science**>

**Physics**

**13 - 14**

**Direct Current (D.C) Circuit**

Calculating the values for current, voltage and resistance in series circuit and parallel circuit

1. Find out what is the reading on A1 and A2, if the current flowing through the main wire is 6A (the bulbs are identical).

NOTE: The current in the diagram flows in one single wire. The ammeters A1 and A2 is used to measure current that is flowing through this one single wire.

A. A1=3A & A2=3A

B. A1=6A & A2=6A

C. A1=6A & A2=12A

D. A1=3A & A2=6A

2. Find out what is the reading on A1 and A2, if the current flowing through the main wire is 5A (the bulbs are identical).

NOTE: The current in the diagram flows in two wire lines. The ammeters A1 and A2 is used to measure current that is flowing through each wire line.

A. A1=2.5A, A2=2.5A

B. A1=2A, A2=3A

C. A1=5A, A2=5A

D. A1=10A, A2=10A

3. Find out what is the reading on A1, if the current flowing through the main wire is 2A and A2 is 0.5A.

NOTE: In the diagram, the main current flows in the two wire lines. The maximum current is in the main wire. In other words, the current in all the separate wires should add up to the main and should not exceed the current in the main.

A. 0.5A.

B. 1.0A.

C. 1.5A.

D. 2A.

4. Find out what is the readings on V1 and V2, if the voltage across the cells is 4V (the bulbs are identical).

NOTE: Remember that a VOLTAGE is present at the battery (as the energy-provider) and at the bulbs (as the energy-user). Meaning, the battery will supply the voltage which will be given out to the bulbs around A SINGLE LOOP. In other words, the voltage will be divided amongst all bulbs in ONE LOOP - The bulb total voltages SHOULD NOT added up exceeding the supplied voltage.

A. V1=4V & V2=4V

B. V1=2V & V2=2V

C. V1=1V & V2=3V

D. V1=8V & V2=8V

5. Find out what is the readings on V1 and V2, if the voltage across the cells is 3V (the bulbs are identical).

NOTE: In the diagram, there are two loops. EACH LOOP has a battery as the energy-provider and one bulb as the energy-user. Meaning, the battery will supply the voltage which will be given out to the only bulb in it's loop.

A. V1=1.5V & V2=1.5V

B. V1=2V & V2=1V

C. V1=6V & V2=6V

D. V1=3V & V2=3V

6. Find out what is the readings on V1, V2 and V3, if the voltage across the cells is 2V (the bulbs are identical).

NOTE: In the diagram, there are 2 loops.

First loop: The voltage supplied is given to only 1 bulb.

Second loop: The voltage supplied is given to two bulbs.

A. V1=1.5V, V2=1.5V & V3=1.5V

B. V1=2V, V2=4V & V3=4V

C. V1=2V, V2=1V & V3=1V

D. V1=4V, V2=2V & V3=2V

7. Calculate the effective resistance, RT, of the following circuit, if R1 is 2Ω and R2 is 4Ω.

NOTE: Remember that to find the effective resistance RT,

In series:

RT = R1 + R2

In parallel:

1/RT = 1/R1 + 1/R2

A. 1.3Ω

B. 2Ω

C. 4Ω

D. 6Ω

8. Calculate the effective resistance, RT, of the following circuit, if R1 is 2Ω and R2 is 3Ω.

NOTE: Remember that to find the effective resistance RT,

In series:

RT = R1 + R2

In parallel:

1/RT = 1/R1 + 1/R2

A. 5Ω

B. 3Ω

C. 2Ω

D. 1.2Ω