Brainscape's Knowledge GenomeTM

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


See full index

FM Chem 11 > P8 - Physics on the move > Flashcards

P8 - Physics on the move Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

How long ago was the big bang?

A

13.8 billion years ago

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

What happens when a light source moves away from you?

A
  • Red shift: The wavelength of light that is emitted INCREASES, DECREASING the frequency.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What happens when a light source moves toward you?

A
  • Blue shift: The wavelength of light that is emitted DECREASES, INCREASING the frequency.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the Big Bang Model?

A
  • Scientists believe the universe started from the initial singularity, a point extremely dense and smaller than the size of an atom, which contained all the energy and matter in the universe.
  • This then suddenly expanded 13.7 billion years ago.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Evidence for the Big Bang

A
  • In the 1960s scientists discovered that there was microwaves radiation coming from all direction, which was radiation left over from the Big Bang.
  • This is called “Cosmic Microwave Background Radiation” (CMBR).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define Planets

A

Object that are spherical because of gravity, that orbit around the sun.

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

Define Comets

A

Objects made of ice and dust in orbit around the sun, usually with very long, thin orbits (elliptical, often travel near the end of the solar system).

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

Order of planets in the solar system

A
  • Mercury
  • Venus
  • Earth
  • Mars
  • Jupiter
  • Saturn
  • Uranus
  • Neptune
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Asteroid belt

A
  • In between Mars and Jupiter, there is an asteroid belt, which is a cluster of asteroids.
  • Asteroids are pieces of rock left over from the formation of the solar system.
  • They contain a dwarf planet called Ceres.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How was the Sun formed? What is it made of?

A
  • The Sun is a huge cloud of dust and hydrogen gas.
  • Gravity pulled the dust and hydrogen gas together, making the central core very hot.
  • Eventually, particles were hot enough for nuclear fusion to occur.
  • There is a balance between the gravitational attraction inward and the expansion of hot gases outward.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are asteroids made of?

A

Mainly rock and metals.

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

Define Nebula

A
  • Giant cloud of dust and gas in space.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the formation of protostars.

A
  • Over time, the force of gravity in a nebula pulls the dust and gas together, to form a protostar.
  • As more and more particles collide and join the protostar, it gets bigger and bigger, making the force of gravity stronger.
  • The gravity also squeezes the protostar, making it more dense.
  • This means particles insides a protostar collide more and raises their temperature.
  • When the temperature and pressure is high enough, nuclear fusion can occur, releasing massive amounts of energy.
  • At this point, we call something a ‘main-sequence star’.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What stage is our sun currently in (life cycle of stars)

A
  • The sun is currently a main-sequence star.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What happens at the end of the main-sequence?

A
  • Stars runs out of fuel, nuclear fusion stops.
  • Force of gravity makes the star collapse.
  • This then increases pressure and temperature, inducing fusion.
  • Star expands again, forming a Red Giant or Red Super Giant.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What factor determines how much a star expands at the end of the main-sequence?

A
  • The size of the star
  • Small/Medium Stars: Red Giant
  • Large Stars: Red Super Giant
17
Q

What happens after a red giant is formed?

A
  • Eventually, it becomes unstable, and expels it outer layers of dust & gas.
  • It leaves behind a ‘white dwarf’, a hot and dense solid core that doesn’t do any fusion.
18
Q

What’s the reason behind the name ‘White Dwarf’?

A
  • The emit lots of life.
  • They are very small.
19
Q

What happens after a white dwarf is formed?

A
  • Over time, the white dwarfs gets cooler and darker, as it emits all its energy.
  • It transitions into a black dwarf, as it no longer has enough energy to emit light and so becomes dark.
20
Q

What happens after a red super giant is formed?

A
  • Red Super Giants began to shine brighter, as they undergo more nuclear fusion.
  • After several cycles of contraction, and expansion, they eventually explode in a supernova.
  • A supernova forms elements heavier than iron that are ejected into the universe.
21
Q

What happens after a supernova?

A
  • Very large stars condense into an ultra-dense core, called a neutron star.
  • Incredibly massive stars collapse completely to form a black hole.
22
Q

Geostationary Orbit Satellites

A
  • 24 hours for one orbit
  • 36,000km above the Earth’s surface
  • Remains in a fixed position above the Earth’s equator
  • Used for satellite television, communications
23
Q

Polar Orbit Satellites

A
  • 2 hours for one orbit
  • 2000km above the Earth’s surface
  • Orbits of the Earth’s poles
  • Used for weather, military (spying), observation of the Earth
24
Q

Describe P waves

A
  • Longitudinal waves
  • They can pass through solids and liquids
  • Travel faster than S waves
25
Q

Describe S waves

A
  • Transverse waves
  • Can ONLY travel through solids
  • Travel in curved paths, due to density changes in the Earth.
26
Q

What equipment measures seismic waves?

A
  • Seismometers
27
Q

Describe where & why S waves can/cannot be detected

A
  • The S-wave shadow zone (usually on the other side of the world opposite the core).
  • This is because S waves cannot pass through a liquid, so the Earth must contain a liquid core.
28
Q

Describe where & why P waves can/cannot be detected

A
  • P wave shadow zones.
  • This is because P waves travel faster in solids than in liquids.
  • So, the P waves slow down when they enter the liquid outer core.
  • This makes them refract, when they enter/leave the outer core.
  • This also confirms the outer core is a liquid.
  • Faint P waves can be detected in the P wave shadow zone, so the earth contains a solid inner core.
29
Q

How do we know the earth has a liquid outer core, and a solid inner core?

A
  • S-waves cannot travel through the outer core, so it must be a liquid.
  • Faint P waves can be detected in the P wave shadow zone, so the earth must contain a solid inner core.
  • P waves refract when they enter/leave the outer core, so the outer core is a liquid.
30
Q

What is the voltage and frequency of mains power (domestic supply)?

A

230V
50Hz

31
Q

What are three different wires in an appliance, and their colours/uses?

A
  • Live wire (brown)
  • Neutral wire (blue)
  • Earth wire (green and yellow)
  • Live & Neutral wire make a complete circuit.
  • Earth wire is not connected to mains, it’s connected to the ‘Earth’, which is usually a large metal pole buried in the ground.
32
Q

Safety features in metal casing

A
  • If the live wire becomes loose, it can touch metal casing, and make it ‘live’.
  • To stop this from happening, the earth wire connects the case to the pole so current flows to the Earth through the wire, not you.
  • Casing can be made of plastic so no current flows. These appliances are ‘double insulated’.
  • Fuses are used, so they melt to switch off the current.
33
Q

Biofuels

A

Renewable fuels that come from living material, such as wood, ethanol, sugar, or methane (from sewage).

34
Q

Sources of non-renewable energy

A
  • The Sun (solar energy)
  • Tides
  • Wind
  • Hot rocks beneath the ground (geothermal energy)
  • Water high up, such as behind dams. (hydroelectric)
35
Q

SI units for joule (joule - petajoule)

A
  • Power of 1: Joule
  • Power of 3: Kilo-
  • Power of 6: Mega-
  • Power of 9: Giga-
  • Power of 12: Tera-
  • Power of 15: Peta-
36
Q

SI units for joule (joule - femtojoule)

A
  • Power of -3: Milli-
  • Power of -6: Micro-
  • Power of -9: Nano-
  • Power of -12: Pico-
  • Power of -15: Femto-
37
Q

What do individuals/governments consider when deciding about which energy sources to use?

A
  • Cost: Setting up, removing, maintaining
  • Effect on environment: Pollution, how it looks for locals
  • Contribution to climate change
  • How long the sources last (sustainability)
38
Q

Describe the use of transformers in the national grid

A
  • Step-up transformers increase the p.d to nearly 400,000V reduce heating effect (energy lost by heat), making the distribution of electricity more efficient.
  • Step-down transformers decrease the voltage to 230V for use in home.

FM Chem 11 (12 decks)

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