Brainscape's Knowledge GenomeTM

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


See full index

physics > all energy - yr9 > Flashcards

all energy - yr9 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Physics flashcards Physics 101 flashcards
1
Q

non renewable resources 2

A

cannot be replenished once used
fossil fuels
nuclear

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

renewable resources 7

A 
easy to replace or replenish
biofuel
solar
wind
wave
tidal
geothermal
hydroelectric
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

nuclear

A 
energy released when atoms break apart - nuclear fission
\+ doesnt release CO2/SO2
\+ produces lots of energy
\+ available always
- non-renewable
- expensive
- leaves behind radioactive waste
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

fossil fuels

A

produced when living material breaks down forming coal(plant life), oil or gas(animal life)
burnt in a power station to create energy
chemical -> heating path -> kinetic -> electric path
+ available readily
+ easy to produce energy from
- non-renewable
- releases CO2/SO2
- increasing cost

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

biofuel/ biomass

A

plant matter breaking down - like fossil fuels
chemical -> heat path -> Kinetic-> electrical path
+less SO2 released than fossil fuel
-uses crop land

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

solar

A 
harness energy from the sun
radiation path->chemical-> electrical path
\+cheap to run
\+no connection to national grid
\+no CO2/SO2
- not always sunny
- expensive to buy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

wind

A 
uses KE to spin turbine + run generator
KE -> electrical path
\+ cheap to run
\+ no CO2/SO2
- expensive to build
- destroys habitat
- only works when windy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

wave

A 
uses KE to spin turbine
KE -> electrical path
\+no CO2/SO2
\+cheap to run
\+ constant source
- no power output
- destroys habitat
- doesn't work in storms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

tidal

A 
the movement of tides is used to produce electricity
KE -> electrical path
\+ no CO2/SO2
\+ cheap to run
\+ reliable - always tides
- has to be by sea
- expensive set up
- ruins habitat
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

geothermal

A

core of earth releases thermal energy
thermal -> mechanical pathway -> electrical pathway
+ no CO2/SO2
- large holes dug (impacts environment)

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

hydroelectric

A 
water trapped behind damn can be released to produce energy
gravitational -> mechanical path-> Kinetic -> electrical path
\+ cheap to run
\+ no CO2/SO2
\+ can be switched on when needed
- habitat damage
- block ports
- produces methane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how a power station works

A

fuel is heated - boils water into steam
steam turns turbine
turbine turns generator
electricity transferred via national grid

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

conduction

A

SOLIDS
heat is transferred by particles to neighbouring particles
- pass on vibrations
- by free electrons (metals - conductors)
non-metals - lots of space and irregular pattern - heat moves slowly - insulators - prevent conduction
metals - closely regularly packed - vibrations + free electrons - fast heat transfer

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

convection

A

LIQUIDS AND GAS - particles free to move

heat energy is carried by particles

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

convection current

A

rising of hot particles (more energy - spread away - less dense)
particles move from heat source and cool down
sinking of cool particles (less energy - closer - more dense)

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

radiation

A

TRANSPARENT MATERIALS + VACUUM - no particles required
transfer of heat via. infra-red rays
matt black - absorb heat - best emitter
shiny white - reflects heat - poor emission
thin flat - radiates energy faster than fat

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

temp

A

measure of how quickly individual particles are vibrating/ moving in an object
Kelvin (K) Celsius (C) Fahrenheit (F)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

heat energy

A

total amount of energy contained in an object

cup of tea has a higher temp but contains less heat than an object (smaller - less energy particles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

thermos flask - keep contents hot/cold 5

A
  • stopper - convection (heat cant rise)
  • vacuum - conduction + convection (no particles)
  • silver coating - radiation (reflects heat prevents emitting or absorption)
  • double glass shell - conduction ( glass - insulator)
  • casting - conduction (plastic - insulator + cold to touch)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

double glazing - reduce heat loss

A

air is trapped between two layers of glass

air is insulator - stops heat escaping by conduction + convection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

ways of reducing heat loss - house

A
  • carpet - conduction (insulator - floor)
  • cavity walls/insulation - conduction (traps air)
  • draught proofing - convection (stop air going out)
  • double glazing - conduction ( trap air)
  • hot water tank jacket - conduction (insulating layer)
  • thick curtains - conduction + radiation (through windows)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

benefit of penguins huddling

A

conserve heat
stops conduction
shelters from winds - act as barrier
every penguin looses heat but gains it from other penguins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

penguins prevent heat loss

A
  • huddle - conduction + convection (insulates them)
  • back skin - radiation (absorbs heat keeping warm)
  • white skin - radiation (reflects off heat + doesnt emit (loose) heat)
  • feathers - conduction (trap air - insulates)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

conduction rod

A
  • copper end - lets heat get to end - spread heat throughout - conductor
  • wood end - burnt - trapped heat - insulator
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

conduction star

A

ball of wax on end of each rod - which drops first shows best conductor

26
Q

metal vs plastic structure

A
  • metal - same size - even spacing
  • > some metals have closer particles - easier for the heat to be transferred
  • plastic - diff sizes - uneven groups
27
Q

convection tube

A

shows movement of water

  • water is heated
  • particles separate
  • water is less dense - rises
  • cold more dense water fills its place
  • setting up a convection current
28
Q

smoke box - convection

A

demonstrates convection in gas

  • flame heats air
  • particles spread
  • air above flame is less dense - rises
  • cold more dense air takes its place
  • convection current
29
Q

hot air balloon

A
  • flame heats air particles
  • balloon expands
  • particles rush out balloon - more energy - less particles in the balloon - less dense
  • balloon rises
30
Q

leslies cube

A 
metal box with 4 different colour sides
(black, shiny, white)
filled with hot water
highest temp= white
lowest temp= shiny
31
Q

reducing heat loss

A

conduction - insulate
convection - lid
radiation - shiny cover - foil

32
Q

efficiency equation

A

Useful energy output (J)/ total energy input(J) x 100

33
Q

efficiency

A

how effective a transfer is (more energy transferred to a useful store the better)
measured as a percentage

34
Q

sankey diagrams

A

A scaled diagram that shows the total input, the wasted output and the useful output (indicated by width of the arrows)

35
Q

wasted energy

A

Energy that is not usefully transferred

is transferred to a store outside the system e.g. thermal store of surroundings

36
Q

work done

A

when energy is transferred from one store to another

37
Q

work done equation (J)

A

force (N) x distance moved (m)

38
Q

power (W) equation (given to you)

A 
energy transferred (J) / time (s)
OR work done (J) / time (s)
39
Q

power

A

amount of energy transferred per second

in watts

40
Q

GPE (J) equation

A

mass (kg) x gravitational field strength (N/kg) x height (m)
Ep = m x g x h
(must be in kg and m)

41
Q

g on earth

A

10N/kg

42
Q

gravitational potential energy

A

stores when work is done to lift an object up

in Joules

43
Q

KE (J) equation

A

1/2 x mass (kg) x velocity^2 (m/s)

Ek = 1/2 m x v^2

44
Q

KE

A

the energy an object has due to its motion

depends on how fast it’s moving

45
Q

rollercoasters

A

maximum GPE =when your at the top
when let go GPE -> KE
how high the hill is controls how fast you go

46
Q

law of conservation of energy

A

energy cannot be created or destroyed
since the start of the universe the total amount of energy has stayed the same
we can only move energy around from store to store (via. pathways) to make things happen

47
Q

energy is measured in

A

Joules (J)

48
Q

stores 8

A 
Chemical,
thermal,
elastic potential,
electrostatic,
nuclear,
gravitational potential
, kinetic,
magnetic
49
Q

pathways 4

A

Radiation,
electrical,
heating,
mechanical

50
Q

chemical store

A

energy stored in a SUBSTANCES to be USED LATER

e.g. batteries, fossil fuels

51
Q

thermal store

A

energy stored in the MOVEMENT OF PARTICLES within a substance
e.g. flask, radiator

52
Q

elastic potential store

A

energy stored in STRECHED objects

e.g. STRETCHED elastic band

53
Q

electrostatic store

A

energy stored by ELECTRICALLY CHARGED objects

e.g. charged ballon stuck to a wall

54
Q

nuclear store

A

energy stored IN ATOMS

e.g. nuclear missile, nuclear power station

55
Q

gravitational potential store

A

energy stored in objects SUSPENDED in gravitational fields

e.g. ball on a shelf

56
Q

kinetic store

A

energy stored in MOVING objects

e.g. moving car, someone running

57
Q

magnetic store

A

energy stored in MAGNETIC fields

e.g. fridge magnet attached to fridge

58
Q

radiation pathway

A

light, microwaves and sound

e.g. torch, star, phone screen

59
Q

mechanical pathway

A

when a force acts and something MOVES

e.g. crane LIFTING a parcel

60
Q

heating pathway

A

e.g. a stove HEATING baked beans

61
Q

electrical pathway

A

e.g. a battery POWERING a lamp

62
Q

bar model

A

bar chart used to represent energy in stores before and after (always have same total energy)

physics (19 decks)

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