Physics — A-Level

Physical Quantities — Structured Questions (Cambridge International A-Level Physics): Exam Questions

Exam code:9702

8 questions · 59 marks · ≈ 59 min

Guided practice

14 markseasy

1 mark

State what is meant by a physical quantity.

Your answer

1 mark

State one physical quantity that can be represented by the symbol $ρ$ .

Your answer

1 mark

State one physical quantity that can be represented by the capital letter $P$ or the lowercase letter $p$ .

Your answer

1 mark

Extract:

State one physical quantity that can be represented by the symbol $$\rho$$. A physical quantity that can be represented by the symbol $$\rho$$ is: Density OR Resistivity State one physical quantity that can be represented by the capital letter $$P$$ or the lowercase letter $$p$$. A physical quantity that can be represented by $$P$$ or $$p$$ is: Pressure; Momentum; Power

Explain how the quantities represented by $ρ$ , $p$ , or $P$ can be distinguished from each other.

Your answer

How did you do?/ 4

26 markseasy

3 marks

Complete Table 1.1 to show the name and symbol of each physical quantity and the corresponding unit.

Table 1.1

physical quantity	symbol	unit
velocity	$v$	m s^-1
	$W$	N m
stress	$σ$
		kg m^-3

Your answer

3 marks

Calculate a reasonable estimate for the work done by a person lifting a dining room chair 1.0 m above the ground.

Your answer

How did you do?/ 6

39 markseasy

3 marks

A physics student is investigating the properties of materials. She has a stack of 500 sheets of paper and needs to determine the thickness of a single sheet.

(i) Describe a method she could use to find the thickness of one sheet of paper without using a micrometer.

(2 marks)

(ii) State an appropriate unit for the thickness of one sheet of paper.

(1 mark)

Your answer

3 marks

The student then investigates simple harmonic motion using a mass-spring system. She wishes to determine the period of oscillation of the system.

Describe a method the student could use to obtain an accurate value for the period of one complete oscillation.

Your answer

1 mark

During a break in her experiments, the student scrunches up a sheet of paper and throws it horizontally from shoulder height across the laboratory.

Estimate the horizontal distance travelled by the paper ball before it hits the floor.

Your answer

2 marks

Extract:

During a break in her experiments, the student scrunches up a sheet of paper and throws it horizontally from shoulder height across the laboratory. Estimate the horizontal distance travelled by the paper ball before it hits the floor.

The student then throws a tennis ball of the same size using the same technique from the same height.

State whether the tennis ball travels a greater horizontal distance than the paper ball. Explain your answer.

Your answer

How did you do?/ 9

412 marksmedium

2 marks

Estimate the speed of an apple as it hits the ground after falling from a tree.

Your answer

2 marks

Estimate the number of kilowatt-hours used by a lightbulb if switched on for a whole day.

Your answer

4 marks

Estimate the density, in g cm⁻³, of the head of an adult person.

Your answer

4 marks

The radius of the Earth is approximately 6.4 × 10⁶ m.

Estimate the number of people it would take to circle the Earth holding hands.

Your answer

How did you do?/ 12

512 marksmedium

3 marks

X–ray pulsars are detected by X–ray telescopes on a satellite in low Earth orbit 2000 km above the surface of the Earth.

Calculate the number of cubic millimetres (mm³) in a volume of 2000 km³.

Your answer

3 marks

X–rays from a pulsar travel at the speed of light and are detected on Earth with a wavelength of 8.0 nm.

Calculate the frequency of the X–rays. Give your answer to an appropriate number of significant figures.

Your answer

3 marks

Extract:

X–rays from a pulsar travel at the speed of light and are detected on Earth with a wavelength of 8.0 nm. Calculate the frequency of the X–rays. Frequency, f = 3.75 × 10^16 Hz.

X–rays from the nearest pulsar PSR J0109–1431 take 8.82 Gs to travel to Earth.

Calculate the number of oscillations of the X–rays from the pulsar to the surface of the Earth. Give your answer to an appropriate number of significant figures.

Your answer

3 marks

Extract:

X–rays from the nearest pulsar PSR J0109–1431 take 8.82 Gs to travel to Earth.

Show the distance from Earth to PSR J0109–1431 is around 280 light years.

Your answer

How did you do?/ 12

68 marksmedium

1 mark

Define the term physical quantity.

Your answer

3 marks

Physical quantities have symbols and units. Indicate, with a tick (✓), which of the following are not valid physical quantities.

kinetic energy $E_{k}$ measured in kg m² s^-2	`square`
pressure $P$ measured in N kg⁻¹	`size 36px square`
Young modulus* * $E$ measured in Pa	`square`
frequency $f$ measured in s	`square`
specific heat capacity* * $c$ measured in J kg⁻¹	`square`
weight $W$ measured in kg m s^-2	`square`

Your answer

4 marks

Complete the table providing reasonable estimates for some physical quantities.

quantity	estimated magnitude
Weight of an adult human
	3600 s
Wavelength of green light
	20 °C

Your answer

How did you do?/ 8

74 markshard

Complete Table 1.1 to show the SI base unit of each physical quantity and a reasonable estimate of the order of magnitude.

Table 1.1

physical quantity	SI base unit	order of magnitude
acceleration of free-fall on Earth (g)	m s⁻²
Stefan-Boltzmann constant (σ)		10⁻⁷
speed of a β particle
specific heat capacity of water (c)

Your answer

How did you do?/ 4

84 markshard

Complete Table 2.1 to show a reasonable estimate of the order of magnitude of each physical quantity and the corresponding unit.

Table 2.1

quantity	order of magnitude	unit
mass of a car		kg
thickness of a sheet of paper		mm
density of air (at room temperature and pressure)		g cm⁻³
time between two heartbeats		s

Your answer

How did you do?/ 4

physical quantity

symbol

unit

velocity

v

m s^-1

W

N m

stress

σ

kg m^-3

39 markseasy

3 marks

A physics student is investigating the properties of materials. She has a stack of 500 sheets of paper and needs to determine the thickness of a single sheet.

(i) Describe a method she could use to find the thickness of one sheet of paper without using a micrometer.

(2 marks)

(ii) State an appropriate unit for the thickness of one sheet of paper.

(1 mark)

Your answer

3 marks

The student then investigates simple harmonic motion using a mass-spring system. She wishes to determine the period of oscillation of the system.

Describe a method the student could use to obtain an accurate value for the period of one complete oscillation.

Your answer

1 mark

During a break in her experiments, the student scrunches up a sheet of paper and throws it horizontally from shoulder height across the laboratory.

Estimate the horizontal distance travelled by the paper ball before it hits the floor.

Your answer

2 marks

Extract:

The student then throws a tennis ball of the same size using the same technique from the same height.

State whether the tennis ball travels a greater horizontal distance than the paper ball. Explain your answer.

Your answer

How did you do?/ 9

kinetic energy

E_{k}

measured in kg m² s^-2

square

pressure

P

measured in N kg⁻¹

size 36px square

Young modulus* *

E

measured in Pa

square

frequency

f

measured in s

square

specific heat capacity* *

c

measured in J kg⁻¹

square

weight

W

measured in kg m s^-2

square

quantity

estimated magnitude

Weight of an adult human

3600 s

Wavelength of green light

20 °C

physical quantity

SI base unit

order of magnitude

acceleration of free-fall on Earth (g)

m s⁻²

Stefan-Boltzmann constant (σ)

10⁻⁷

speed of a β particle

specific heat capacity of water (c)

quantity

order of magnitude

unit

mass of a car

thickness of a sheet of paper

density of air

(at room temperature and pressure)

g cm⁻³

time between two heartbeats