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PHYSICS – Energy
LEARNING
OBJECTIVES
1.7.1 Energy
Core
• Identify changes in kinetic,
gravitational potential, chemical, elastic
(strain), nuclear and internal energy
that have occurred as a result of an
event or process
• Recognise that energy is transferred
during events and processes, including
examples of transfer by forces
(mechanical working), by electrical
currents (electrical working), by heating
and by waves
• Apply the principle of conservation of
energy to simple examples
Supplement
• Recall and use the expressions kinetic
energy = ½mv2
and change in
gravitational potential energy = mg∆h
• Apply the principle of conservation of
energy to examples involving multiple
stages
• Explain that in any event or process
the energy tends to become more spread
out among the objects and surroundings
(dissipated)
Work, work, work ……
Work, work, work ……
When a force
moves an object
it does work and
energy is
transferred to
the object.
Work, work, work ……
When a force
moves an object
it does work and
energy is
transferred to
the object.
Energy supplied
Work done
Energy
transferred
Work, work, work ……
When a force
moves an object
it does work and
energy is
transferred to
the object.
Energy supplied
Work done
Energy
transferred
Amount of energy transferred (J) = Work done (J)
Work, work, work ……
When a force
moves an
object it does
work and
energy is
transferred
to the object.
The man shovelling is doing work. If he does 600J of
work, then he loses 600J of energy. The substance being
shovelled gains energy - but not the full 600J, as some is
lost as sound and heat.
Work
• Work is done whenever a force makes
something move.
Work
• Work is done whenever a force makes
something move.
• The greater the force, and the greater
the distance moved, the more work is
done.
Work
• Work is done whenever a force makes
something move.
• The greater the force, and the greater
the distance moved, the more work is
done.
• When work is done energy is
transferred from one form into
another.
Work
Work done = force x distance
W = F x d
Work is measured in Joules
Work
Work done = force x distance
Eg. if a 4 N force moves a distance of 3m
W = 4 x 3 = 12 J
Work
W
d
F
Work
Force
Distance
Work
W
d
F
Work
Force
Distance
W = F x d
Work
W
d
F
Work
Force
Distance
W = F x d
F = W
d
Work
W
d
F
Work
Force
Distance
W = F x d
F = W
d
d = W
F
Types of energy……
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Energy contained
in food or fuel,
eg. Food and
petrol
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Energy contained
in food or fuel,
eg. Food and
petrol
Energy in the flow
of electrons, eg.
A battery
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Energy contained
in food or fuel,
eg. Food and
petrol
Energy in the flow
of electrons, eg.
A battery
Energy released
when the nucleus
of an atom splits
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Energy contained
in food or fuel,
eg. Food and
petrol
Energy in the flow
of electrons, eg.
A battery
Energy released
when the nucleus
of an atom splits
Energy given out
by any hot object,
eg. The Sun, light
bulb.
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Energy contained
in food or fuel,
eg. Food and
petrol
Energy in the flow
of electrons, eg.
A battery
Energy released
when the nucleus
of an atom splits
Energy given out
by any hot object,
eg. The Sun, light
bulb.
Energy given out
by vibrating
objects, eg. A
loud speaker
Types of energy……
Types of
energy
Kinetic
GPE
Elastic
PE
Chemical
Electrical
Nuclear
Light
Sound
Heat
Energy in a moving
object, eg. A
moving car
Energy due to the
height of an
object, eg. A
skier on a slope
Energy in a
stretched or
compressed object,
eg. a spring
Energy contained
in food or fuel,
eg. Food and
petrol
Energy in the flow
of electrons, eg.
A battery
Energy released
when the nucleus
of an atom splits
Energy given out
by any hot object,
eg. The Sun, light
bulb.
Energy given out
by vibrating
objects, eg. A
loud speaker
Energy contained
in any hot or
warm object, eg.
Burning coal
Types of energy……
Gravitational
Potential Energy
Kinetic energy
Potential Energy
• Potential energy is the energy due to height.
• Potential energy (PE) = mass x g x height
• (g is the gravitational constant = 10 m/s2
)
Potential Energy
• Eg. A sheep of mass 47kg is slowly raised
through a height of 6.3m. Find the gain in
potential energy.
• PE = mgh = 47 x 10 x 6.3 = 2961J
• As an object falls, its potential energy is
changed into kinetic energy.
• Kinetic energy GAINED = Potential energy
LOST
Kinetic Energy
• Kinetic energy is the energy of movement.
• Anything moving has kinetic energy.
• Kinetic energy (KE) = ½ x mass x velocity2
• Or KE = ½ x mass x velocity x velocity
Kinetic Energy
• Eg. A car of mass 2450kg is travelling at
38m/s. Calculate its kinetic energy.
• KE = ½ x 2450 x 382
= 1,768,900J
• KE depends upon mass and speed, so a larger
object travelling at greater speed has a bigger
KE.
Types of energy……
Let’s have a
look at a more
challenging
calculation
involving GPE
and KE
Eg. A mouldy tomato of mass 140g is dropped
from a height of 1.7m. Calculate its speed as it
hits the floor.
1. PE lost = mgh = 0.14 x 10 x 1.7 = 2.38 J
2. So KE gained = PE lost = 2.38 J = ½ mv2
3. So, 2.38 = ½ x 0.14 x v2
= 0.07 x v2
4. So, 2.38 = v2
0.07
5. So, 34 = v2
; v = 5.38 m/s
LEARNING
OBJECTIVES
1.7.1 Energy
Core
• Identify changes in kinetic,
gravitational potential, chemical, elastic
(strain), nuclear and internal energy
that have occurred as a result of an
event or process
• Recognise that energy is transferred
during events and processes, including
examples of transfer by forces
(mechanical working), by electrical
currents (electrical working), by heating
and by waves
• Apply the principle of conservation of
energy to simple examples
Supplement
• Recall and use the expressions kinetic
energy = ½mv2
and change in
gravitational potential energy = mg∆h
• Apply the principle of conservation of
energy to examples involving multiple
stages
• Explain that in any event or process
the energy tends to become more spread
out among the objects and surroundings
(dissipated)
Energy transfer
Energy transfer
Energy is transferred from cells and other sources
Energy transfer
Energy is transferred from cells and other sources
Anything that supplies electricity is also supplying energy.
So cells, batteries, generators, etc. all transfer energy to
the charge in the wire, which then transfers it to the
components or devices in the circuit:
M
Energy transfer
Energy is transferred from cells and other sources
Anything that supplies electricity is also supplying energy.
So cells, batteries, generators, etc. all transfer energy to
the charge in the wire, which then transfers it to the
components or devices in the circuit:
M
230 V
Power supply
provides the
energy
Kinetic
energy
Light
energy
Heat
energy
Sound
energy
Energy transfer
We can also use a Sankey diagram to show energy transfer
Energy transfer
We can also use a Sankey diagram to show energy transfer
A Sankey diagram makes it easier to see how much input
energy is being usefully employed compared with how much
is being wasted. The thicker the arrow, the more energy it
represents.
Energy transfer
We can also use a Sankey diagram to show energy transfer
A Sankey diagram makes it easier to see how much input
energy is being usefully employed compared with how much
is being wasted. The thicker the arrow, the more energy it
represents.
ENERGY
INPUT
USEFUL SOUND ENERGY
USEFUL LIGHT ENERGY
WASTED HEAT ENERGY
Eg. Television set
Energy transfer
We can also use a Sankey diagram to show energy transfer
Energy transfer
We can also use a Sankey diagram to show energy transfer
Eg. Throwing a
stone
Chemical
energy in
muscles
Kinetic
energy
Potential
energy
Kinetic
energy
Stone thrown
upwards
Stone at highest
point
Stone hits the
ground
Thermal energy
(wasted in body)
Thermal energy
(wasted because
of air resistance)
Thermal energy
Thermal energy
(in ground and
stone)
Sound
Describe the energy changes
taking place in a roller
coaster ride.
As it travels around the
track, energy changes from
GPE to KE and back again
Total energy at any one time
= KE + GPE
When there are no resistive
forces, total energy remains
constant.
This is known as the
principle of conservation of
energy.
Energy cannot be created or
destroyed, but only changed
from one form into another.
Usually, some energy is used
up doing work against
friction and air resistance 
lost as heat.
LEARNING
OBJECTIVES
1.7.1 Energy
Core
• Identify changes in kinetic,
gravitational potential, chemical, elastic
(strain), nuclear and internal energy
that have occurred as a result of an
event or process
• Recognise that energy is transferred
during events and processes, including
examples of transfer by forces
(mechanical working), by electrical
currents (electrical working), by heating
and by waves
• Apply the principle of conservation of
energy to simple examples
Supplement
• Recall and use the expressions kinetic
energy = ½mv2
and change in
gravitational potential energy = mg∆h
• Apply the principle of conservation of
energy to examples involving multiple
stages
• Explain that in any event or process
the energy tends to become more spread
out among the objects and surroundings
(dissipated)
PHYSICS – Energy
TYPES OF ENERGY, energy resources and electricity generation grade 9 edexcel igcse

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TYPES OF ENERGY, energy resources and electricity generation grade 9 edexcel igcse

  • 2. LEARNING OBJECTIVES 1.7.1 Energy Core • Identify changes in kinetic, gravitational potential, chemical, elastic (strain), nuclear and internal energy that have occurred as a result of an event or process • Recognise that energy is transferred during events and processes, including examples of transfer by forces (mechanical working), by electrical currents (electrical working), by heating and by waves • Apply the principle of conservation of energy to simple examples Supplement • Recall and use the expressions kinetic energy = ½mv2 and change in gravitational potential energy = mg∆h • Apply the principle of conservation of energy to examples involving multiple stages • Explain that in any event or process the energy tends to become more spread out among the objects and surroundings (dissipated)
  • 4. Work, work, work …… When a force moves an object it does work and energy is transferred to the object.
  • 5. Work, work, work …… When a force moves an object it does work and energy is transferred to the object. Energy supplied Work done Energy transferred
  • 6. Work, work, work …… When a force moves an object it does work and energy is transferred to the object. Energy supplied Work done Energy transferred Amount of energy transferred (J) = Work done (J)
  • 7. Work, work, work …… When a force moves an object it does work and energy is transferred to the object. The man shovelling is doing work. If he does 600J of work, then he loses 600J of energy. The substance being shovelled gains energy - but not the full 600J, as some is lost as sound and heat.
  • 8. Work • Work is done whenever a force makes something move.
  • 9. Work • Work is done whenever a force makes something move. • The greater the force, and the greater the distance moved, the more work is done.
  • 10. Work • Work is done whenever a force makes something move. • The greater the force, and the greater the distance moved, the more work is done. • When work is done energy is transferred from one form into another.
  • 11. Work Work done = force x distance W = F x d Work is measured in Joules
  • 12. Work Work done = force x distance Eg. if a 4 N force moves a distance of 3m W = 4 x 3 = 12 J
  • 18. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat
  • 19. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car
  • 20. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope
  • 21. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring
  • 22. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring Energy contained in food or fuel, eg. Food and petrol
  • 23. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring Energy contained in food or fuel, eg. Food and petrol Energy in the flow of electrons, eg. A battery
  • 24. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring Energy contained in food or fuel, eg. Food and petrol Energy in the flow of electrons, eg. A battery Energy released when the nucleus of an atom splits
  • 25. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring Energy contained in food or fuel, eg. Food and petrol Energy in the flow of electrons, eg. A battery Energy released when the nucleus of an atom splits Energy given out by any hot object, eg. The Sun, light bulb.
  • 26. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring Energy contained in food or fuel, eg. Food and petrol Energy in the flow of electrons, eg. A battery Energy released when the nucleus of an atom splits Energy given out by any hot object, eg. The Sun, light bulb. Energy given out by vibrating objects, eg. A loud speaker
  • 27. Types of energy…… Types of energy Kinetic GPE Elastic PE Chemical Electrical Nuclear Light Sound Heat Energy in a moving object, eg. A moving car Energy due to the height of an object, eg. A skier on a slope Energy in a stretched or compressed object, eg. a spring Energy contained in food or fuel, eg. Food and petrol Energy in the flow of electrons, eg. A battery Energy released when the nucleus of an atom splits Energy given out by any hot object, eg. The Sun, light bulb. Energy given out by vibrating objects, eg. A loud speaker Energy contained in any hot or warm object, eg. Burning coal
  • 29. Potential Energy • Potential energy is the energy due to height. • Potential energy (PE) = mass x g x height • (g is the gravitational constant = 10 m/s2 )
  • 30. Potential Energy • Eg. A sheep of mass 47kg is slowly raised through a height of 6.3m. Find the gain in potential energy. • PE = mgh = 47 x 10 x 6.3 = 2961J • As an object falls, its potential energy is changed into kinetic energy. • Kinetic energy GAINED = Potential energy LOST
  • 31. Kinetic Energy • Kinetic energy is the energy of movement. • Anything moving has kinetic energy. • Kinetic energy (KE) = ½ x mass x velocity2 • Or KE = ½ x mass x velocity x velocity
  • 32. Kinetic Energy • Eg. A car of mass 2450kg is travelling at 38m/s. Calculate its kinetic energy. • KE = ½ x 2450 x 382 = 1,768,900J • KE depends upon mass and speed, so a larger object travelling at greater speed has a bigger KE.
  • 33. Types of energy…… Let’s have a look at a more challenging calculation involving GPE and KE
  • 34. Eg. A mouldy tomato of mass 140g is dropped from a height of 1.7m. Calculate its speed as it hits the floor. 1. PE lost = mgh = 0.14 x 10 x 1.7 = 2.38 J 2. So KE gained = PE lost = 2.38 J = ½ mv2 3. So, 2.38 = ½ x 0.14 x v2 = 0.07 x v2 4. So, 2.38 = v2 0.07 5. So, 34 = v2 ; v = 5.38 m/s
  • 35. LEARNING OBJECTIVES 1.7.1 Energy Core • Identify changes in kinetic, gravitational potential, chemical, elastic (strain), nuclear and internal energy that have occurred as a result of an event or process • Recognise that energy is transferred during events and processes, including examples of transfer by forces (mechanical working), by electrical currents (electrical working), by heating and by waves • Apply the principle of conservation of energy to simple examples Supplement • Recall and use the expressions kinetic energy = ½mv2 and change in gravitational potential energy = mg∆h • Apply the principle of conservation of energy to examples involving multiple stages • Explain that in any event or process the energy tends to become more spread out among the objects and surroundings (dissipated)
  • 37. Energy transfer Energy is transferred from cells and other sources
  • 38. Energy transfer Energy is transferred from cells and other sources Anything that supplies electricity is also supplying energy. So cells, batteries, generators, etc. all transfer energy to the charge in the wire, which then transfers it to the components or devices in the circuit:
  • 39. M Energy transfer Energy is transferred from cells and other sources Anything that supplies electricity is also supplying energy. So cells, batteries, generators, etc. all transfer energy to the charge in the wire, which then transfers it to the components or devices in the circuit: M 230 V Power supply provides the energy Kinetic energy Light energy Heat energy Sound energy
  • 40. Energy transfer We can also use a Sankey diagram to show energy transfer
  • 41. Energy transfer We can also use a Sankey diagram to show energy transfer A Sankey diagram makes it easier to see how much input energy is being usefully employed compared with how much is being wasted. The thicker the arrow, the more energy it represents.
  • 42. Energy transfer We can also use a Sankey diagram to show energy transfer A Sankey diagram makes it easier to see how much input energy is being usefully employed compared with how much is being wasted. The thicker the arrow, the more energy it represents. ENERGY INPUT USEFUL SOUND ENERGY USEFUL LIGHT ENERGY WASTED HEAT ENERGY Eg. Television set
  • 43. Energy transfer We can also use a Sankey diagram to show energy transfer
  • 44. Energy transfer We can also use a Sankey diagram to show energy transfer Eg. Throwing a stone Chemical energy in muscles Kinetic energy Potential energy Kinetic energy Stone thrown upwards Stone at highest point Stone hits the ground Thermal energy (wasted in body) Thermal energy (wasted because of air resistance) Thermal energy Thermal energy (in ground and stone) Sound
  • 45. Describe the energy changes taking place in a roller coaster ride.
  • 46. As it travels around the track, energy changes from GPE to KE and back again
  • 47. Total energy at any one time = KE + GPE
  • 48. When there are no resistive forces, total energy remains constant.
  • 49. This is known as the principle of conservation of energy.
  • 50. Energy cannot be created or destroyed, but only changed from one form into another.
  • 51. Usually, some energy is used up doing work against friction and air resistance  lost as heat.
  • 52. LEARNING OBJECTIVES 1.7.1 Energy Core • Identify changes in kinetic, gravitational potential, chemical, elastic (strain), nuclear and internal energy that have occurred as a result of an event or process • Recognise that energy is transferred during events and processes, including examples of transfer by forces (mechanical working), by electrical currents (electrical working), by heating and by waves • Apply the principle of conservation of energy to simple examples Supplement • Recall and use the expressions kinetic energy = ½mv2 and change in gravitational potential energy = mg∆h • Apply the principle of conservation of energy to examples involving multiple stages • Explain that in any event or process the energy tends to become more spread out among the objects and surroundings (dissipated)