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WorksheetsElectric Circuits Summative
Total questions: 25
Worksheet time: 2hrs 5mins
Two resistors of resistance 10 Ω and 20 Ω are connected in parallel to a cell.
The energy dissipated in the 10 Ω resistor in one second is Q. What is the energy dissipated in one second in the 20 Ω resistor?
Q/4
Q/2
4Q
2Q
An ideal ammeter is used to measure the current in a resistor. Which of the following gives the resistance of an ideal ammeter and the way it is connected to the resistor?
Resistance = infinite, Connection = in parallel
Resistance = infinite, Connection = in series
Resistance = zero, Connection = in parallel
Resistance = zero, Connection = in series
The circuit shows a resistor R connected in series with a 20 V battery and a resistor of resistance 10 Ω. The current is 1.0 A.
Which of the following is the resistance of R?
1.0 Ω
2.0 Ω
10 Ω
20 Ω
Resistors of resistance R, R and 3R are connected to a cell. The diagram shows three currents, Ix, Iy and Iz in the resistors. What is the correct relationship between the currents?
Ix = Iy
Iy = 3 Iz
Iz = 3 Ix
Ix = Iy + 3 Iz
A heating coil is connected to a 10 V battery. The power dissipated in the coil is 25 W. What is the resistance of the coil?
0.25 Ω
2.5 Ω
4.0 Ω
250 Ω
In a lightning flash a charge of 15 C flows in 0.5 m s. What is the average current?
33 μA
7.5 mA
30 A
30 kA
A filament lamp and a semiconducting diode have the voltage-current characteristics shown and are connected in parallel.
What is the resistance of the lamp and the resistance of the diode when the current in each device is 2.0 A?
Lamp 1.0 Ω and Diode 0.25 Ω
Lamp 1.0 Ω and Diode 0.50 Ω
Lamp 0.50 Ω and Diode 0.25 Ω
Lamp 0.50 Ω and Diode 0.50 Ω
Three resistors of resistance R are connected in parallel across a battery of potential difference V. What is the rate at which the battery supplies energy?
3RV2
9RV2
R9V2
R3V2
A current of 50.0 A flows through a cross-section of a wire. After six hours, what is the total number of all of the electrons which have passed through the cross section?
Charge of electron = 1.60 x 10-19 C
1.08 x 106 electrons
6.75 x 1024 electrons
1.125 x 1023 electrons
1.45 x 1016 electrons
The volt is equivalent to which combination of units?
J C-1
C J-1
W C-1
C W-1
Calculate the current in a wire if 240 C of charge pass a given point in 2 minutes.
2 A
120 A
480 A
28800 A
What is the total resistance of the combination of four 10 Ω resistors connected as shown?
5 Ω
10 Ω
20 Ω
40 Ω
A 9.0 V battery is connected to a light bulb. Calculate the energy transferred in the light bulb when 20 C of charge flows through it in 2 minutes.
0.45 J
2.2 J
180 J
21600 J
A 100 W lamp connected to the 230 V mains is replaced by a lamp which has twice the resistance. The power of the new lamp is:
25 W
50 W
200 W
400 W
Calculate the total resistance of this combination.
21
47
68
357
Calculate the total circuit resistance when both switches are closed.
1/2 R
2/3 R
R
2R
Which switch combination dissipates the most energy in a given time?
A open. B open
A open. B closed
A closed. B open
A closed. B closed
Both voltmeters have a resistance of 10 MΩ. The reading on V1 is 6 V and the reading on V2 is zero. Explain these readings.
Calculate the resistance of the bulb when the potential difference across it is 6 V.
0.20 Ω
0.21 Ω
4.8 Ω
4.9 Ω
Describe the change in the resistance of the bulb as the potential difference across it is increased.
Remains constant
Decreases
Increases
There isn't enough information
Calculate the resistance of resistor R.
(a)
A current of 0.0400 A flows in a conductor for 10.0 seconds.
If 8.60 J of energy are transferred to the conductor in this time, calculate the potential difference across the conductor.
(a)
The reading on the voltmeter is 8.0 V and the resistance of R2 is 60 Ω.
Calculate the resistance of R1.
(a)
A lamp is rated 4.5 V, 2.0 W.
Calculate the current in the lamp when it is operated at its correct working voltage.
(a)
The filament of the lamp in X breaks and the lamp no longer conducts. What happens to the voltmeter reading and the brightness of lamp Y?
Voltmeter reading increases & Lamp Y brighter
Voltmeter reading decreases & Lamp Y brighter
Voltmeter reading increases & Lamp Y dimmer
Voltmeter reading decreases & Lamp Y dimmer
