Q1:
A student has a resistor of unknown resistance. She places the resistor in series with a source of variable potential difference. Using an ammeter, she measures the current through the resistor at different potential differences and plots her results on the graph as shown in the diagram. What is the resistance of the resistor?
Q2:
A 10 Ω resistor in a circuit has a potential difference of 5 V across it. What is the current through the resistor?
Q3:
A 2 300 Ω resistor in a circuit has a current of 100 mA through it. What is the potential difference across the resistor?
Q4:
A resistor in a circuit has a potential difference of 10 V across it. The current through the resistor is 10 A. What is the resistance of the resistor?
Q5:
What kind of circuit component has a lower resistance if the temperature around the component is higher?
- A An ohmic conductor
- B An LED
- C A fuse
- D A diode
- E A thermistor
Q6:
A resistor in a circuit has a potential difference of 20 V across it. The current through the resistor is 0.4 mA. What is the resistance of the resistor?
Q7:
The diagram shows a circuit consisting of a cell providing a potential difference of 20 V and a resistor with a resistance of 5 Ω. What is the current through the resistor?
Q8:
An electric heater that has a resistance of 17.7 Ω is connected to a 230 V power supply. Given that the electron charge , the number of electrons passing through the heater every minute is . Give your answer in scientific notation to two decimal places.
- A electrons
- B electrons
- C electrons
- D electrons
Q9:
Consider the circuit below. When changing the value of , which of the following graphs represents the relation between and the reading of the ammeter?
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A
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B
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C
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D
Q10:
A student sets up the circuit shown in the diagram. She uses an ammeter to measure the current through the circuit and gets a value of 2.5 A. She then uses a voltmeter to measure the potential difference across the resistor and gets a value of 10 V. What is the value of the resistance of the resistor?
Q11:
How many millivolts are there in 0.5 volts?
Q12:
Consider the circuit shown below.
When changing the value of , which of the following graphs represents the relation between and the reading on the voltmeter?
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A
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B
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C
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D
Q13:
Which of the following is the correct unit for potential difference?
- A Ohm
- B Ampere
- C Joule
- D Watt
- E Volt
Q14:
If electrons move through a conductor that has a potential difference of 16 V across it within 3 seconds, then the resistance of this conductor equals . Let the electron charge .
- A 230 Ω
- B 10 Ω
- C 26 Ω
- D 1 Ω
Q15:
Adel wants to find out the resistance of a resistor. He connects the resistor to a variable potential difference power source and uses an ammeter to find the current through the resistor. His results are shown in the table. What is the resistance of the resistor?
| Potential Difference (V) | 3 | 6 | 9 | 12 | 15 |
|---|---|---|---|---|---|
| Current (mA) | 50 | 100 | 150 | 200 | 250 |
Q16:
How many volts are there in 20 kilovolts?
Q17:
What is wrong with the circuit shown in the diagram?
- A The current is shown as flowing in the wrong direction.
- B The current will be different on each side of the resistor; therefore, the ammeter cannot give a reading.
- C Ammeters and voltmeters must always be used together.
- D Ammeters should not be connected in parallel.
- E The signs of the battery are the wrong way around.
Q18:
What is wrong with the circuit shown in the diagram?
- A The signs of the battery are the wrong way around.
- B Voltmeters and ammeters must always be used together.
- C The voltmeter will lower the resistance of the circuit.
- D Voltmeters should be connected in parallel across a component.
- E The current is shown as flowing in the wrong direction.
Q19:
Ammeters should always be connected in . Voltmeters should always be connected in .
- A series, series or parallel
- B parallel, parallel
- C series, series
- D series, parallel
- E parallel, series
Q20:
What kind of circuit component has a lower resistance if the light incident upon it is at a higher intensity?
- A An LED
- B A thermistor
- C A fuse
- D An LDR
- E A diode
Q21:
Which of the following is the correct unit for electrical resistance?
- A Volt
- B Joule
- C Watt
- D Ampere
- E Ohm
Q22:
How many ohms are there in 1 kilohm?
Q23:
Each of the following diagrams shows a circuit consisting of a cell and a resistor. In which circuit does the resistor have a resistance of 30 Ω?
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A
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B
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C
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D
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E
Q24:
Which of the following is the correct formula for Ohm’s Law?
- A
- B
- C
- D
- E
Q25:
A student sets up the circuit shown in the diagram. He sees that the ammeter reads 0.05 A. What value does the voltmeter read?
