1. Motion, forces and energy

1.1 Physical quantities and measurement techniques

1.2 Motion

1.3 Mass and weight

1.4 Density

1.5.1 Effects of forces

1.5.2 Turning effect of forces

1.5.3 Centre of gravity

1.6 Momentum

1.7.1 Energy

1.7.2 Work

1.7.3 Energy resources

1.7.4 Power

1.8 Pressure

2. Thermal physics

2.1.1 States of matter

2.1.2 Particle model

2.1.3 Gases and the absolute scale of temperature

2.2.1 Thermal expansion of solids, liquids and gases

2.2.2 Specific heat capacity

2.2.3 Melting, boiling and evaporation

2.3.1 Conduction

2.3.2 Convection

2.3.3 Radiation

2.3.4 Consequences of thermal energy transfer

3. Waves

3.1 General properties of waves

3.2.1 Reflection of light

3.2.2 Refraction of light

3.2.3 Thin lenses

3.2.4 Dispersion of light

3.3 Electromagnetic spectrum

3.4 Sound

4. Electricity and magnetism

4.1 Simple phenomena of magnetism

4.2.1 Electric charge

4.2.2 Electric current

4.2.3 Electromotive force and potential difference

4.2.4 Resistance

4.2.5 Electrical energy and electrical power

4.3.1 Circuit diagrams and circuit components

4.3.2 Series and parallel circuits

4.3.3 Action and use of circuit components

4.4 Electrical safety

4.5.1 Electromagnetic induction

4.5.2 The a.c. generator

4.5.3 Magnetic effect of a current

4.5.4 Force on a current-carrying conductor

4.5.5 The d.c. motor

4.5.6 The transformer

5. Nuclear physics

5.1.1 The atom

5.1.2 The nucleus

5.2.1 Detection of radioactivity

5.2.2 The three types of nuclear emission

5.2.3 Radioactive decay

5.2.4 Half-life

5.2.5 Safety precautions

6. Space physics

6.1.1 The Earth

6.1.2 The Solar System

6.2.1 The Sun as a star

6.2.2 Stars

6.2.3 The Universe

IGCSE Physics 4.2.4 Resistance Question Bank

[Maximum number: 1]

A student does an experiment to investigate the resistance of a metal wire.
The graph shows the results from the experiment.

What is plotted on the x-axis?

diameter of the wire

length of the wire

temperature of the wire

current in the wire

[Maximum number: 1]

A wire has a uniform circular cross-sectional area.
Which statement is correct?

The resistance of the wire is directly proportional to its cross-sectional area and inversely proportional to its diameter.

The resistance of the wire is directly proportional to its cross-sectional area and inversely proportional to its length.

The resistance of the wire is directly proportional to its length and inversely proportional to its cross-sectional area.

The resistance of the wire is directly proportional to its length and inversely proportional to its diameter.

[Maximum number: 1]

A laboratory has a standard wire of known resistance. It also has other wires, made from the same material as the standard wire, but of different lengths and diameters.

Which wire would definitely have a resistance of less than the standard wire?

wire length

wire diameter

longer

larger

longer

smaller

shorter

larger

shorter

smaller

[Maximum number: 1]

A student determines the resistance of resistor R. She uses a circuit including a voltmeter and an ammeter.

Which circuit does she use?

[Maximum number: 1]

A piece of metal wire X with a uniform diameter has resistance R.

A second piece of wire Y is made of the same metal and has a uniform diameter. Y has double the cross-sectional area of X and half the length of X.

What is the resistance of Y?

$\frac{R}{4}$

$\frac{R}{2}$

4 R

[Maximum number: 1]

The diagram shows the current-voltage graph for a metal wire.

What can be deduced from the graph?

As voltage increases, the temperature of the wire increases.

As voltage increases, the temperature of the wire decreases.

As voltage increases, the resistance of the wire increases.

As voltage increases, the resistance of the wire remains constant.

[Maximum number: 1]

A student is investigating a resistance wire.
She measures the current in a 50 cm length of resistance wire.

The student repeats the experiment using a 100 cm length of the same resistance wire.
What is the effect of this change on the current in the circuit and on the resistance of the wire?

effect on

current

effect on

resistance

decreases

increases

decreases

increases

[Maximum number: 1]

The diagram shows a circuit used to control the potential difference (p.d.) across a lamp.
The variable resistor is adjusted until the p.d. across the lamp is 6.0 V .
The current in the lamp is 0.5 A .

What is the resistance of the lamp?

$0.083 \Omega$

$3.0 \Omega$

$6.5 \Omega$

$12.0 \Omega$

[Maximum number: 1]

A resistor and a battery are connected in series.
The value of the resistor is $20 \Omega$ .
The potential difference (p.d.) of the battery is 4.0 V .
What is the current in the resistor?

$0.20 \mathrm{~A}$

$4.0 \mathrm{~A}$

$5.0 \mathrm{~A}$

$80 \mathrm{~A}$

(a)

On Fig. 6.1, sketch the current-voltage graph of a filament lamp and explain its shape.

Fig. 6.1

explanation

[ 3 ]

(b)

Fig. 6.2 shows an electric circuit.

Fig. 6.2

[ 2 ]

(i)

Calculate the current in the $4.2 \Omega$ resistor.

current =

[ 2 ]

0 selected

Question 25

Question 25

Question 26

Question 26

Question 26

Question 26

Question 26

Question 26

Question 26

Question 6

Question 6(a)

Question 6(b)

Question 6(b)(ii)