DC Circuits Self Test 3 | Physics

Which one of the circuits shown in the diagram below can be used to determine the resistance of $R$ ?

A) I
B) II
C) III
D) IV
A car's starter motor draws a current of $100\; A$ at $12,0 \;V$ when starting the engine. The mechanical power required to turn the engine is $960 \;W.$ At what rate is energy from the battery converted to non-mechanical forms of energy?

A) $240 \;W$
B) $960\; W$
C) $1200 \;W$
D) $1440\; W$
In the circuit shown below one of the bulbs blew. The result was that all bulbs stopped glowing. Which bulb blew?

A) bulb a
B) bulb b
C) bulb c
D) bulb d
Three resistors are connected to a battery as shown in the diagram. At which point in the circuit is the current the smallest?

A) a
B) b
C) c
D) d
In the circuit shown below, the resistance of the ammeter, the battery and the connecting wires are negligible. The voltmeter has a very high resistance. The ammeter reads $1,5\; A.$ What is the reading on the voltmeter?

A) $4 \;V$
B) $6\; V$
C) $8\; V$
D) $12 \;V$
Two resistors are connected in parallel as shown in the diagram. The current flowing through the ammeter is:

A) $0,6\; A$
B) $1,5\; A$
C) $2,5\; A$
D) $14,4 \;A$

Consider the circuit shown to the right. If switch

$S$ is closed, the readings on the voltmeter and ammeter will change as follows:

Diagram of circuit with battery, switch, ammeter and voltmeter

Diagram of circuit with battery, switch, ammeter and voltmeter

Answer	Voltmeter reading	Ammeter reading
A	becomes zero	remains the same
B	becomes zero	increases
C	remains the same	decreases
D	decreases	increases

The circuit below shows two identical bulbs,

$L$ and

$M,$ which are connected to a battery and a variable resistor

$R.$ How will the brightness of the bulbs be affected if the resistance of

$R$ is increased?

Diagram of a circuit with battery, identical bulbs and variable resistor

Diagram of a circuit with battery, identical bulbs and variable resistor

Answer	bulb L	bulb M
A	dimmer	brighter
B	dimmer	dimmer
C	dimmer	the same
D	brighter	the same

The battery in the circuit has an internal resistance r and an emf E. The resistance of the ammeter and the conductors is negligible and the voltmeter has a high resistance — The battery in the circuit has an internal resistance $r$ and an emf $E.$ The resistance of the ammeter and the conductors is negligible and the voltmeter has a high resistance.
The information given above refers to questions 9 and 10

When the switch

$S$ is closed, the …

Answer	Voltmeter reading	Ammeter reading
A	decreases	decreases
B	decreases	increases
C	increases	decreases
D	increases	increases

When the switch

$S$ is closed the power in the resistors

$R_1$ and

$R_2$ …

Answer	Power in $R_1$	Power in $R_2$
A	decreases	decreases
B	decreases	increases
C	increases	decreases
D	increases	increases

Check your answers

D
A
C
C
B
C
B
A
B
C