CAIE IGCSE Physics 4.3.2 Series and Pa…l Circuits

Covered syllabus points

4.3.2.1—Current at every point in a series 4.3.2.2—How to construct and use series and 4.3.2.3—Combined e.m.f. of several sources in 4.3.2.4—Combined resistance of two or more 4.3.2.5—That, for a parallel circuit, the 4.3.2.6—Combined resistance of two resistors 4.3.2.7—Advantages of connecting lamps in 4.3.2.8—Circuit rules: (a) current into a 4.3.2.9—The sum of the currents into a 4.3.2.10—Combined resistance of two resistors

[Maximum number: 1]

The diagram shows a circuit containing a cell, a lamp and two ammeters.

Figure for Question 1 — CAIE IGCSE Physics

The current reading on ammeter 2 is 0.20 A .
What is the name for this type of circuit and what is the reading on ammeter 1 ?

type of circuit

reading on ammeter 1

series

0.20 A

series

greater than 0.20 A

parallel

0.20 A

parallel

greater than 0.20 A

[Maximum number: 1]

The circuit shown contains three switches and four lamps P, Q, R and S.

Figure for Question 2 — CAIE IGCSE Physics

Which switches must be closed to light only lamps P and R ?

switch 1 only

switch 1 and switch 2

switch 1 and switch 3

switch 2 and switch 3

[Maximum number: 1]

Fig. 8.2 shows a circuit.

Fig. 8.2

The three cells are identical and have zero resistance.
The resistors $R_{1}, R_{2}$ and $R_{3}$ are identical.
The reading on the voltmeter is 6.0 V .
When the diode is conducting, it has zero resistance and zero potential difference (p.d.) across it.

Determine the e.m.f. of one cell.

e.m.f. =

[Maximum number: 3]

Fig. 10.1 shows a circuit containing a filament lamp of resistance $0.30 \Omega$ and two resistors, each of resistance $0.20 \Omega$ .

Fig. 10.1

Calculate the combined resistance of the lamp and the two resistors.
resistance =

$1 / \mathrm{R}_{\mathrm{p}}=1 / \mathrm{R}_{1}+1 / \mathrm{R}_{2} \mathrm{OR}\left(\mathrm{R}_{\mathrm{p}}=\right) 1 /\left(1 / \mathrm{R}_{1}+1 / \mathrm{R}_{2}\right) \mathrm{OR}\left(\mathrm{R}_{\mathrm{p}}=\right) \mathrm{R}_{1} \mathrm{R}_{2} /\left(\mathrm{R}_{1}+\mathrm{R}_{2}\right) \mathrm{OR}(0.2 \times 0.3) /(0.2+0.3) \mathrm{OR} 0.6 \times 0.2$ $\left(\mathrm{R}_{\mathrm{p}}=\right) 0.12(\Omega)$ $\left(\mathrm{R}_{\mathrm{t}}=0.12 \Omega+0.20 \Omega=\right) 0.32 \Omega$

[Maximum number: 1]

A student uses four ammeters P, Q, R and S to measure the current in different parts of the circuit shown.

Figure for Question 5 — CAIE IGCSE Physics

Which two ammeters read the largest current?

P and Q

P and R

R and Q

R and S

[Maximum number: 2]

Fig. 8.1 shows a circuit that contains a battery of electromotive force (e.m.f.) 6.0 V , an ammeter, a $20 \Omega$ resistor and component X .

Fig. 8.1

(a)

A second resistor is connected into the circuit in parallel with the $20 \Omega$ resistor.

[ 2 ]

(i)

State how the combined resistance of the two resistors in parallel compares with the resistance of each of the resistors on its own.

[ 1 ]

(ii)

The p.d. across the two parallel resistors is changed and the current in the battery for each value of the p.d. is measured. A second line could be drawn on Fig. 8.2 to indicate how the current measured by the ammeter depends on the p.d. across the two resistors in parallel.

State how the second line differs from the original line. You are not expected to draw this second line.

[ 1 ]

[Maximum number: 1]

Fig. 2.1 shows solar-powered traffic warning lights.

Fig. 2.1

The energy from the solar cell is stored in a battery.

The two lights in Fig. 2.1 are connected in parallel.

State one advantage of a parallel connection in a lighting circuit.

[Maximum number: 4]

(a)

Fig. 6.2 shows an electric circuit.

Fig. 6.2

[ 4 ]

(i)

Calculate the reading on the voltmeter.
voltmeter reading =

[ 2 ]

(ii)

Determine the current in the $2.1 \Omega$ resistor.

current =

[ 1 ]

(iii)

Determine the reading on the ammeter.

ammeter reading =

[ 1 ]

[Maximum number: 3]

Fig. 7.1 shows a circuit that contains a battery, a switch, a voltmeter and three $40 \Omega$ resistors, $\mathrm{R}_{1}$ , $R_{2}$ and $R_{3}$ .

Fig. 7.1

The switch is open and resistors $R_{1}$ and $R_{2}$ form a potential divider.

The reading on the voltmeter is 7.5 V .

The switch is closed.

Calculate the resistance of the complete circuit.

resistance =

All question bank results loaded

CAIE IGCSE Physics 4.3.2 Series and Parallel Circuits Topic Practice

Covered syllabus points

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question (a)

Question (i)

Question (ii)

Question 7

Question 8

Question (a)

Question (i)

Question (ii)

Question (iii)

Question 9