# Worksheet: Using Potential Dividers

In this worksheet, we will practice finding the output voltage of a potential divider and describing how potential dividers can be used in sensing circuits.

**Q1: **

What type of electronic component could be used instead of one of the resistors in a potential divider to create a light-sensing circuit?

- AAn LED
- BA diode
- CA light-dependent resistor
- DA fuse
- EA thermistor

**Q3: **

Isabella has a light bulb that requires a 12 V potential difference across it in order to work. She only has an 18 V battery to power it. Which of the following pairs of resistors can be used to create a potential divider to power the light bulb?

- A 48 Ω and 36 Ω
- B 12 kΩ and 2 kΩ
- C 10 kΩ and 5 kΩ
- D 8 kΩ and 6 kΩ
- E 200 Ω and 500 Ω

**Q4: **

A potential divider has an input voltage of 48 V. The resistance of the second resistor, , is 100 kΩ. The output voltage is drawn across the second resistor, . What resistance must the first resistor, , have in order to produce an output voltage of 32 V?

**Q5: **

A potential divider has an input voltage of 36 V. The resistance of the first resistor, , is 48 Ω. The output voltage is drawn across the second resistor, . What resistance must the second resistor have in order to produce an output voltage of 18 V?

**Q6: **

A potential divider consists of two resistors, and . The resistance of is 200 Ω, and the resistance of is 400 Ω. The output voltage is drawn across . What input voltage is needed to produce an output voltage of 12 V?

**Q7: **

The diagram shows a circuit for a potential divider. The value of is 24 kΩ. The value of is 32 kΩ. What input voltage is needed to produce an output voltage of 8 V?

**Q8: **

The diagram shows a circuit for a potential divider. If the input voltage, , is 30 V, what value of is needed to produce an output voltage of 20 V?

**Q9: **

A potential divider has an input voltage of 24 V. The resistance of the first resistor, , is 25 Ω. The resistance of the second resistor, , is 75 Ω. The output voltage is drawn across the second resistor. What is the value of the output voltage?

**Q10: **

The diagram shows a circuit for a potential divider. If the input voltage is 12 V, what value of is needed to produce an output voltage of 4 V?

**Q11: **

The diagram shows a circuit for a potential divider. If the input voltage, , is equal to 15 V, what is the value of the output voltage, ?

**Q12: **

The diagram shows a circuit for a potential divider consisting of a thermistor and a variable resistor. This circuit can be used as a temperature sensor. The input voltage, , is 12 V.

The variable resistor is set to a resistance of 10 kΩ. At a temperature of , the thermistor has a resistance of 50 kΩ. What is the value of the output voltage when the temperature is ?

- A 10 V
- B 6 V
- C 9.6 V
- D 2 V
- E 2.4 V

The variable resistor is kept at a resistance of 10 kΩ. At a temperature of , the thermistor has a resistance of 500 kΩ. What is the value of the output voltage when the temperature is ? Give your answer to 2 decimal places.

- A 11.43 V
- B 11.4 V
- C 0.57 V
- D 12 V
- E 0.6 V

In order for the output voltage to register as a value of 1 in the logic circuit that it is connected to, it must be at least 98% of the value of the input voltage. What is the lowest value of resistance that the variable resistor can be set to in order to achieve this output voltage at ? Give your answer in kilohms.

- A 30 kΩ
- B 24.5 kΩ
- C 0.49 kΩ
- D 0.51 kΩ
- E 24 kΩ

**Q13: **

The diagram shows a circuit for a potential divider that consists of a resistor and a thermistor. This potential divider could be used as part of a temperature-sensing circuit. The resistance of the thermistor decreases as the temperature increases.

As the temperature of the thermistor increases, the output voltage . As the temperature of the thermistor decreases, the output voltage .

- Adecreases, increases
- Bincreases, increases
- Cincreases, stays the same
- Dincreases, decreases
- Edecreases, decreases