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 6.2.3 The Universe Question Bank

[Maximum number: 1]

A galaxy is $3.0 \times 10^{20} \mathrm{~km}$ from the Earth.
At which speed is the galaxy moving away from the Earth?

$660 \mathrm{~km} / \mathrm{s}$

$6600 \mathrm{~km} / \mathrm{s}$

$660 \mathrm{~m} / \mathrm{s}$

$6600 \mathrm{~m} / \mathrm{s}$

[Maximum number: 1]

Two quantities define the Hubble constant $H_{0}$ .
- the speed at which the galaxy is moving away from the Earth v
- the distance of the galaxy from the Earth d

What is the relationship between v and d and what is the current estimate for $H_{0}$ ?

relationship

current estimate for $H_{0}$

v is proportional to d

$2.2 \times 10^{-18} \mathrm{~s}^{-1}$

v is proportional to $\frac{1}{d}$

$2.2 \times 10^{-18} \mathrm{~s}^{-1}$

v is proportional to d

$3.0 \times 10^{8} \mathrm{~m} / \mathrm{s}$

v is proportional to $\frac{1}{d}$

$3.0 \times 10^{8} \mathrm{~m} / \mathrm{s}$

[Maximum number: 1]

Which statement does not describe redshift?

All the light emitted from all distant galaxies is at the red end of the spectrum.

The light arriving at the Earth from a receding star is always redshifted.

During redshift, the wavelength of the observed light is longer than it is if the redshift had not occurred.

The light from stars in all distant galaxies is moved towards the red end of the spectrum.

[Maximum number: 1]

What is the definition of the Hubble constant?

the ratio of the speed at which a galaxy is receding from the Earth to its distance from the Earth

the value of the change in wavelength of the galaxy's starlight due to redshift

the constant used to represent the rate of expansion of the Universe in all directions

the estimated constant equal to the age of the Universe

[Maximum number: 1]

Which quantity can be determined using the brightness of a supernova in a distant galaxy?

the speed at which the galaxy is moving away from the Earth

the distance of the galaxy from the Earth

the Hubble constant

the age of the Universe

[Maximum number: 1]

An astronomer observes a distant galaxy.
The table shows how the distance and the speed of recession of the galaxy are determined.
Which row is correct?

distance

speed of recession

brightness of a
supernova in the galaxy

change in wavelength of
starlight from the galaxy

brightness of a
supernova in the galaxy

brightness of
the galaxy

change in wavelength of
starlight from the galaxy

brightness of
the galaxy

brightness of
a supernova

[Maximum number: 1]

A galaxy at a distance of $3.1 \times 10^{21} \mathrm{~km}$ is moving away from the Earth with a speed of $7000 \mathrm{~km} / \mathrm{s}$ .
What is the Hubble constant $H_{0}$ calculated using this data and what is the speed of a galaxy at a distance of $6.2 \times 10^{21} \mathrm{~km}$ from the Earth?

$H_{0} / \mathrm{s}^{-1}$

$\frac{\text { speed of galaxy }}{\mathrm{km} / \mathrm{s}}$

$2.3 \times 10^{-18}$

3500

$2.3 \times 10^{-18}$

14000

$4.4 \times 10^{17}$

3500

$4.4 \times 10^{17}$

14000

[Maximum number: 1]

What is the approximate diameter of the Milky Way?

100000 kilometres

1000000 kilometres

100000 light-years

1000000 light-years

(a)

Describe and explain what can be deduced from cosmic microwave background radiation (CMBR).

[ 3 ]

(a)

A galaxy is moving away from the Earth with a speed of $33000 \mathrm{~km} / \mathrm{s}$ .

The value of the Hubble constant is $2.2 \times 10^{-18}$ per second.
Calculate the distance from the galaxy to the Earth. Give your answer in light-years.
distance = light-years [2]

[ 2 ]

0 selected

Question 39

Question 40

Question 40

Question 40

Question 40

Question 40

Question 40

Question 40

Question 11

Question 11(b)

Question 10

Question 10(d)