Here are notes based on the provided images, which appear to be pages from a
physics textbook discussing various forms of energy:
Page 1 (IMG_0577.jpg, image_5d1623.jpg - focusing on the right page text):
Sound energy:
o Produced when an object vibrates.
o Released into the air (e.g., guitar string plucked, drum skin struck).
o Does not pass through gases, such as air, but through liquids and
solids too.
Electrical energy:
o Movement of electric charges through a conductor (e.g., copper,
graphite).
o Electric charges possess electrical energy (e.g., from a store in a
battery).
o Carried to working parts of a circuit.
o Transferred into a store of light and heat energy (e.g., a lamp).
Internal energy (also called thermal energy):
o All substances are made up of particles.
o Particles possess a certain amount of energy, allowing them to move.
o When a substance is heated, particle movement increases.
o In solids: Particles move backwards and forwards about a fixed
position.
o In liquids: Particles move more quickly and can move past each other.
o In gases: Particles move freely in all directions at high speeds.
o When heated, particles receive more energy and move faster.
Page 2 (IMG_0576.jpg, image_5d15e1.jpg - focusing on the left page figures
and text):
Figure 12.2: Shows objects that store elastic potential energy.
Strain energy (elastic potential energy):
o Some materials can be stretched or squashed, then spring back into
shape (e.g., elastic bands, springs).
o When deformed, they store elastic potential energy.
o This energy allows them to return to their original shape when the force
is removed.
o Examples:
Springs store strain energy when stretched or squashed.
Gases store strain energy when compressed (e.g., in an aerosol
can, for spraying).
Figure 12.3: Illustrates places where strain energy can be stored and
released (e.g., a diver on a diving board, a person on a trampoline, a
stretched bow).
Page 3 (IMG_0575.jpg, image_5d15a3.jpg - focusing on the right page text):
Stores of energy:
o Energy can be classified in different ways (e.g., light, heat, electrical).
o Two main types discussed:
Potential energy: Energy depends on position or state.
Movement energy (Kinetic energy):
Potential energy:
o Various examples exist.
o Gravitational potential energy:
Energy due to attraction between two objects in the universe
(gravity).
Exists between large objects like stars and planets, and even
between small objects like ants walking across the ground.
The size of the force of gravitational force varies and is related
to the mass of the object.
A star has a great deal of mass,1 thus a great deal of gravity.
An ant has very tiny mass and a very tiny force of gravity.
The force of gravity does not affect other ants or objects around
it.
The force of gravity of humans also does not affect anything
around us.
If one object has a large mass and another object has a small
mass, the force of gravity of the large mass is greater2 than the
force of gravity of the small mass.
This difference3 in strength results in the object with the small
mass being pulled towards the object with the large mass.
All objects on Earth have much less mass than the planet, and
the much larger gravitational force of the Earth pulls them
towards the center4 of the planet.
An object positioned above the surface of the Earth possesses
stored energy called gravitational potential energy.
Examples: Plates on a table, books on a shelf, a child at the top
of a slide, an apple growing on a branch. If support is removed,
they move quickly to the Earth's surface and their potential
energy is released and changed into other forms of energy.
