Current, voltage and resistance
Grade 11 Science Worksheet - Building Confidence
Circle the best answer, or write your answer on the line.
A 12 V battery is joined across a 4 kΩ resistor. What current flows, in mA, Ari?
A 5 V battery is joined across a 2.5 kΩ resistor. What current flows, in mA, Bo?
A 9 V battery is joined across a 6 kΩ resistor. What current flows, in mA, Esme?
Circuit schematic (example data): a 6 V battery, a closed switch and one resistor in one loop. Jun reads the schematic. What is the resistor's resistance?
- 0.042 Ω: 0.25 A ÷ 6 V
- 24 Ω: 6 V ÷ 0.25 A
- 5.75 Ω: 6 V − 0.25 A
- 1.5 Ω: 6 V × 0.25 A
Kira reads the schematic. What does the ammeter read?
- 0.15 A: 12 V ÷ 80 Ω, the second resistor alone
- 0.10 A: 12 V ÷ (40 Ω + 80 Ω)
- 0.20 A: 12 V ÷ 60 Ω, the average resistance
- 0.30 A: 12 V ÷ 40 Ω, the first resistor alone
Luz reads the schematic. What does the voltmeter across the 80 Ω resistor read?
- 8 V: 0.10 A × 80 Ω
- 4 V: 0.10 A × 40 Ω
- 6 V, the battery voltage shared equally
- 12 V, the battery voltage
A 470 Ω resistor has 9.4 V across it. What current flows through it, Milo?
- 2 mA, out by a factor of ten
- 0.02 mA, out by a factor of 1,000
- 20 mA: 9.4 V ÷ 470 Ω = 0.020 A
- 200 mA, out by a factor of ten the other way
Why must a voltmeter have a very high resistance, Ren?
- It needs to handle large voltages without overheating
- It draws a tiny current, so it barely changes the circuit
- It must add resistance so it shares the circuit's current
- It measures current, which needs a high resistance
Tala connects an ammeter across a resistor instead of in the loop. What happens?
- Nothing changes; the meter reads the resistor's current
- The ammeter reads zero because no current enters it
- A large current bypasses the resistor through the ammeter
- The resistor carries twice the current
Zee reads the voltage-current graph of a resistor. What is its resistance?
- 20 Ω: 8 V ÷ 0.4 A
- 3.2 Ω: 8 V × 0.4 A
- 0.05 Ω: 0.4 A ÷ 8 V
- 8.4 Ω: 8 V + 0.4 A