HW 5

IT equals 0.1 mA in a 3-branch parallel circuit. If I1 = 0.022 mA and I2 = 0.007 mA, I3 = ?

0.071 mA

A three-branch parallel circuit carries a total current of 1.2 mA. If I1 = 0.2 mA and I2 = 0.7 mA, then what is the value of I3?

0.3 mA

In a three-resistor parallel circuit, R1 = 0.22 MΩ and R2 = 1 MΩ. If RT = 0.1166 MΩ, then what is the value of R3?

0.33 M Ω

If three 22 kΩ resistors are connected in parallel across a 10 V source, PT equals ________.

13.6 m W

If a 500 Ω, 1200 Ω and 10 kΩ resistor are connected in parallel across a 25 V source, how much current flows through the 1200 Ω resistor?

20.8 mA

If four 100 W lamps are connected in parallel across a 120 V source, what is the total current?

3.33 A

If there is 100 mA of current flowing into a three-branch parallel circuit and two of the branch currents are 40 mA and 20 mA, the third branch current is ________.

40 mA

If a 1 MΩ resistor, 0.47 MΩ resistor and 0.5 MΩ resistor are connected in parallel across an 18 V source, what is the total current if the 1 MΩ resistor opens?

74.3 μA

If 5 A and 3 A enter a junction from two separate paths, how much current flows out of the junction?

8 A

A parallel circuit can be easily identified because only one end of each component is connected to each other.

False

If one branch of a parallel circuit opens, the total resistance decreases.

False

If three equal resistors are connected in parallel across 12 V, each resistor drops 4 V.

False

PR1 = 0.25 W and PR2 = 1.2 W in a parallel circuit. The total power dissipated is 1.25 W.

False

A formula that applies to a two-branch parallel circuit is ________.

IT = IR1 + IR2

As additional branch resistors are connected in a parallel circuit,

IT increases and RT decreases

In a parallel circuit, total power PT is calculated as:

P1 + P2 + P3 + etc.

If one branch of a parallel circuit shorts, the total resistance decreases.

True

Kirchhoff's Current Law states that the sum of the currents into a junction must equal the sum of the currents out of that junction.

True

Measurement of total current is accomplished with the ammeter in series with the source voltage.

True

The total resistance of four resistors in parallel is always less than the smallest resistance.

True

Total power for a parallel circuit can be determined by the same method as a series circuit.

True

The power dissipated by any branch of a parallel circuit ________.

depends on the voltage and value of the resistor

If you want to measure a load voltage with a DVM, connect the meter ________.

in parallel with the load

To measure the current through one branch of a parallel circuit, the meter is connected ________.

in series with the branch resistor

If one resistor shorts in a parallel circuit, the total current ________.

increases

If one resistor opens in a parallel circuit, the total circuit resistance ________ and the total circuit current ________.

increases, decreases

The current through any branch of a parallel circuit ________.

is inversely proportional to the branch resistance

In a parallel circuit, the largest amount of power is dissipated by:

the smallest resistor.