Series & Parallel Circuits

Series & Parallel Circuits Question Paper 1

Time allowed: 46 minutes

Score: /46

Percentage: /100

Grade Boundaries:

Level GCSE

Subject Physics

Exam Board AQA

Topic Electricity

Sub-topic Series & Parallel Circuits

Booklet Question Paper 1

9 8 7 6 5 4 3 >72% 63% 54% 45% 35% 26% 21%

1 Copyright © 2020 Save My Exams Ltd. All rights reserved.

For more awesome resources, visit us at www.savemyexams.co.uk/

http://www.savemyexams.co.uk/

Q1.

(a) The circuit in Figure 1 shows how an LDR can be used to turn on a circuit when itgets dark.

Figure 1

If the light intensity decreases, what happens to the current and the potential difference across the LDR?

[2 marks]

Potential difference ____________________________________________

Current ______________________________________________________

(b) When the potential difference across the LDR is 3 V, what is its resistance?

Explain your answer.

[2 marks]

Resistance = ________________ Ω

Reason ___________________________________________________________

__________________________________________________________________



(c) When the light gets dimmer, the resistance of the LDR becomes 1000 .Ω

Calculate the current through the LDR when its resistance is 1000 .Ω

Give your answer to 3 significant figures.[4 marks]

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

_________________________________________________________________

Current = ______________ A

[Question Total: 8 marks]



Q2.

A student has four resistors.

Each resistor has a resistance of 100 .Ω

(a) Explain how the resistors should be connected so that the total resistance is as lowas possible.

[2 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

(b) The four resistors are connected in series with a 3 V cell, as shown in Figure 2below.

Figure 2

Calculate the current that flows through the cell.

Give your answer to 3 significant figures.

[3 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

Current = _________________A



(c) Add an ammeter to Figure 2 which would allow the current through the cell to bemeasured.

[2 marks]

[Question total: 7 marks]



Q3.

A student set up the circuit in Figure 3 below.

Figure 3

(a) The ammeter displays a reading of 0.075 A.

Calculate the potential difference across the 80 resistor.Ω[2 marks]

__________________________________________________________________

__________________________________________________________________

Potential difference ___________________ V

(b) Calculate the resistance of resistor R in Figure 3.[3 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

Resistance = _____________ Ω



(c) Switch X is closed.

State what will happen to the total resistance of the circuit and the current throughthe circuit.

[2 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

(d) Calculate the new current through the circuit.[3 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

Current = ________________ A




Q4.

Figure 4 below shows how two resistors can be connected in series or in parallel to a 12 V cell.

The resistors are identical.

Figure 4

(a) Calculate the potential difference across each resistor when the lamps are connectedin series and in parallel.

[2 marks]

In series __________________________________________________________

_________________________________________________________________

In parallel _________________________________________________________

_________________________________________________________________

(b) Give one disadvantage of connecting the lamps in series rather than in parallel.[1 mark]

__________________________________________________________________

__________________________________________________________________



Figure 5 shows how an ammeter can be used to measure the current flowing through the battery for the same circuit.

Figure 5

The reading on the ammeter is 1.6 A.

(c) Add an ammeter to Figure 5 to show how to measure the current through resistor R2.

[1 mark]

(d) The resistors are identical.

State the current through resistor R2.[1 mark]

__________________________________________________________________

__________________________________________________________________




Q5.

Figure 6 shows a fixed resistor connected in series with a variable resistor.

Figure 6

The resistance of the variable resistor can be varied between 100 and 800 .Ω Ω

The graph below in Figure 7 shows how the readings on both voltmeters vary as the resistance of the variable resistance is changed.

Figure 7



(a) Calculate the potential difference of the battery.[2 marks]

__________________________________________________________________

__________________________________________________________________

Potential difference = __________________ V

(b) Use the graph in Figure 7 to determine the resistance of the fixed resistor R in thecircuit shown in Figure 6.

[2 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

Resistance = ___________ Ω

(c) Add an ammeter to Figure 6 above to show how the current through the circuit couldbe measured.

[1 mark]

(d) Calculate the current through the circuit when the resistance of the variable resistor isset to 400 .Ω

[3 marks]

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

__________________________________________________________________

Current = _____________ A




Q6.

The circuit diagram in Figure 8 shows two resistors connected in parallel.

Figure 8

Reading on ammeter A1 = 3 A

Reading on ammeter A2 = 1 A

Using the circuit diagram in Figure 8, answer the questions below:

(a) What is the potential difference across resistor R1?[1 mark]

potential difference = ___________________ V

(b) Calculate the resistance of resistor R1.[2 marks]

__________________________________________________________________

__________________________________________________________________

Resistance = ______________ Ω

(c) What is the current flowing through the variable resistor R2?[1 mark]



Current = ___________________ A

(d) Calculate the resistance of the variable resistor R2.[1 mark]

__________________________________________________________________

__________________________________________________________________

Resistance = __________________ Ω

(e) The resistance of the variable resistor R2 is increased.

What would happen to:

● The current through R2● The potential difference across R2● The current through the battery?

Tick ( ) three boxes [3 marks]

Increase Stay the same Decrease

Current through R2

potential difference across R2

current through the battery




Series & Parallel Circuits

Documents

Transcript of Series & Parallel Circuits