Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IGCSE PHYSICS REVISION > Space Physics Details/Definitions > Flashcards

Space Physics Details/Definitions Flashcards

1
Q

The Earth orbits the Sun once in…

A

approximately 365 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Nature of the rotation of the earth

A

-Rotates on its axis(which is tilted)
-Complete rotation takes approximately 24 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Impact of rotation of the Earth on day and night cycles

A

-In areas where the sun is not facing that side of the Earth, it would be nighttime.
-In areas where the sun is facing that side of the Earth, it would be daytime.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why day and night are not of equal length(in most places in the world)

A

The axis of the Earth is tilted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Why the nature of seasons is periodic

A

Because of the tilt in the Earth’s axis(different parts of the planet are tilted further or closer away from the sun)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Time it takes for the moon to orbit the Earth

A

Approximately one month

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why the moon has phases

A

-As the Moon orbits around the earth, different parts of it are illuminated by the Sun
-As the same side of the Moon always points toward Earth, some of the illuminated part faces away from us

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Structure of the Solar System

A

-The Sun(the only star)
-The eight named planets
-Minor planets(eg. dwarf planets like Pluto and asteroids in the asteroid belt)
-Moons that orbit the planets
-Smaller solar system bodies(eg. comets and natural satellites)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The orbits that planets, minor planets and comets have are…

A

elliptical(oval-shaped)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

The Sun is only at the centre of the orbit when…

A

the orbit is approximately circular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The planets(in order from the sun)

A

-Mercury
-Venus
-Earth
-Mars
-Jupiter
-Saturn
-Uranus
-Neptune

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The four planets nearest to the Sun are…

A

rocky and small(compared to those furthest from the Sun)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The four planets furthest from the Sun are…

A

gaseous and large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

At the surface of a planet, the strength of a gravitational field depends on…

A

the mass of the planet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

the strength of a gravitational field around a planet decreases as…

A

the distance from the planet increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why do planets orbit the Sun

A

The Sun contains most of the mass of the Solar System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Force that keeps an object in orbit around the Sun

A

The gravitational attraction of the Sun

18
Q

As the distance of a planet from the Sun increases…

A

-the strength of the Sun’s gravitational field decreases
-the orbital speeds of the planet decreases

19
Q

An object in an elliptical orbit travels faster when closer to the Sun(T/F)

A

True

20
Q

Features of the Sun

A

-A star of medium size
-Consists mostly of hydrogen and helium
-Radiates most of its energy in the infrared, visible and ultraviolet regions of the electromagnetic spectrum

21
Q

What stars are powered by

A

Nuclear reactions(which give out energy)

22
Q

In stable stars, the nuclear reactions(that power them) involve…

A

the fusion of hydrogen into helium

23
Q

Galaxies are made up of…

A

many billions of stars

24
Q

The galaxy which the Sun is in

A

The Milky Way

25
Q

Astronomical distances are usually measured in…

A

light-years

26
Q

Light-year

A

the distance travelled in (the vacuum of) space by light in one year

27
Q

(In metres) One light-year is equal to…

A

9.5 × 10¹⁵m

28
Q

Life cycle of a star

A

-A star is formed from interstellar clouds of gas and dust that contain hydrogen
-A protostar becomes a stable star when the inward force of gravitational attraction is balanced by an outward force due to the high temperature in the centre of the star
-All stars eventually run out of hydrogen as
fuel for the nuclear reaction
-Most stars expand to form red giants and more massive stars expand to form red supergiants when most of the hydrogen in the centre of the star has been converted to
helium

29
Q

Protostar

A

an interstellar cloud collapsing and increasing in temperature due to its internal gravitational attraction

30
Q

What happens to red giants

A

They form a planetary nebula with a white dwarf star at its centre

31
Q

What happens to red supergiants

A

-They explode as a supernova, forming a nebula containing hydrogen and new heavier elements, leaving behind a neutron star or a black hole at its centre
-The nebula from the supernova may form new stars with orbiting planets

32
Q

Diameter of the Milky Way

A

100,000 light-years

33
Q

Redshift

A

an increase in the observed wavelength of electromagnetic radiation emitted from receding stars and galaxies

34
Q

Redshift in the light from distant galaxies is evidence that…

A

the Universe is expanding

35
Q

Light emitted from distant galaxies appears…

A

redshifted in comparison with light emitted on the Earth

36
Q

Microwave radiation of a specific frequency is observed at all points in space around us(T/F)

A

True

37
Q

Cosmic microwave background radiation (CMBR)

A

microwave radiation that is observed at all points in space around us

38
Q

When was CMBR produced

A

Shortly after the Universe was formed

39
Q

How the speed at which a galaxy is moving away from the Earth can be found

A

By observing the change in wavelength of the galaxy’s starlight due to redshift

40
Q

Hubble constant

A

the ratio of the speed at which the galaxy is moving away from the Earth to its distance from the Earth

41
Q

Estimate for Hubble constant(H₀)

A

2.2 × 10⁻¹⁸

42
Q

Features of the equation:
distance(d)/speed(v) = 1/H₀

A

-Represents an estimate for the age of the Universe
-Is evidence for the idea that all matter in the Universe was present at a single point

IGCSE PHYSICS REVISION (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions