Sci
reviewer!
By mahima
Rithal

TOPICS

ENERGY
THE ABILITY TO DO WORK

The transmission of thermal energy (heat) by the bulk movement of materials
is known as convection.
In FLUIDS, convection occurs (liquids and gases).
In both gases and liquids, convection causes CURRENTS.
As particles migrate from one area to another, they carry thermal energy with
them.
CONVECTION

Heat transfer from one particle of substance to another by direct
particle-to-particle contact.
Conduction occurs largely in solids due to the close packing of the particles.
The particles themselves DO NOT CHANGE PLACE.
The handle of a cooking utensil
CONDUCTION

Electromagnetic waves that are used to transport (thermal) energy.
Radiation is energy that originates from a source and travels at the speed of
light through space.
Radiation must first be absorbed by a substance before it can be felt as heat.
RADIATION

Chemical energy is energy stored within the chemical bonds in matter.
CHEMICAL ENERGY

Kinetic energy is a form of energy that an object or a particle has by reason of
its motion.
Kinetic energy

Potential energy is a type of energy an object has because of its position.
As a function of its location, an item can store energy. When a demolition
machine's heavy ball is held at an elevated position, for example, it stores
energy. Potential energy is the name given to this stored positional energy. A
drawn bow, likewise, can store energy as a function of its posture.
Potential energy

The total of an item's kinetic and potential energy; the energy of an object related to
its motion or location.
Mechanical energy is..

Conduction – transfer of heat energy from one particle to another by direct
contact. (Primarily in solids)
Convection – transfer of heat energy in fluids-gases and liquids) through the
bulk movement of matter from one place to another. (Produces currents)
Radiation – transfer of energy through electromagnetic waves. (Matter is
not required!) (Radiant & infrared radiation from the sun)
Review

Thermal energy always moves from warmer to cooler substances until both
substances have the same temperature.
Forms of energy include mechanical, chemical, electrical, electromagnetic,
thermal, sound, and nuclear energy.
Key points

Renewable
energy
Renewable energy, often known as clean energy, is
generated from naturally regenerated sources or
processes.
01

forms of energy
Solar energy
The sun’s light contains
energy in the form of
electromagnetic waves
Hydroelectric Energy
Hydroelectric plants use falling
water from a dam to turn the turbine
of a generator.
Wind Energy
03
Wind turbines use the momentum of
moving air to quietly turn large
blades that are attached to the
shaft of an efficient electric
generator
Geothermal Energy
The steam is used to drive turbines
of a generator and the generator
produces electricity.
01
04
02
Biomass Energy
Biomass is matter usually thought of as
garbage. This matter includes things like
leaves, tree branches, leftover crops, wood
chips, and bark. It can even include animal
manure and old tires.
05

Non-renewable energy
Nonrenewable energy is produced from resources that
will decrease or will not be replaced for hundreds, if not
millions, of years.
02

forms of energy
Coal Energy
Coal is the product of millions of
years of pressure on organic
matter from plants buried
underground.
Natural Gas Energy
Natural gas reserves often share
space with underground oil reserves,
so the two non-renewable resources
are often extracted at the same
time.
Oil Energy
Crude Oil is referred to as Liquid
Petroleum. It is used for gasoline,
heating oil, and diesel fuel.
In addition, manufacturers utilize oil
for such products as plastics and
industrial chemicals.
Nuclear Energy
It is considered a nonrenewable
form of energy because it takes real
manipulation to split an atom.
01
04
02
03

Light and sound energy

light..
● Light is a form of energy that travels in waves.
● Light waves can travel through empty space, without needing a solid, liquid, or gas
medium.
● Light travels through space at the fastest speed matter and energy can possibly
reach: about 300,000 kilometers (186,000 miles) per second.
● Transparent matter allows light to pass through with almost no disturbance
● When light rays strike matter that is translucent, some light passes through, and
some is either blocked or bent in different directions
● Opaque matter reflects or absorbs all light
● Infrared light has lower energy than ultraviolet light.
● Shadow is formed when an opaque object blocks some
particles of the light to past through.
● A shape of an object always determines the shape of its
shadow. However, the size and shape of the shadow can
change. These changes are caused by the position of the
light source
●
Shadow..

Sound..
● Wave is a disturbance that
transfers energy from one point to
another
● Must travel through a medium, or
substance, in order to transfer
energy.
● The movement of particles by a
wave is called vibration
● Wavelength is the distance
between wave crests or troughs.

Vid but plss don’t cry!!

CREDITS: This presentation template was created by Slidesgo,
including icons by Flaticon, and infographics & images by Freepik
Electricity

● Have neutrons, protons, and electrons.
● Protons are positively charged
● Electrons are negatively charged
Atoms..

● Are located on the outer edges of atoms…they can be moved.
● A concentration of electrons in an atom creates a net negative charge.
● If electrons are stripped away, the atom becomes positively charged.
Electrons…

● Movement of electrons
● Energy is measured in Joules (J)
● Volts (V) – measures how strongly electrons will move
ELECTRICITY IS…

Static electricity is a well-known electric activity that involves the
transmission of charged particles from one body to another.
The build up of an electric charge on the surface of an object.
The charge builds up but does not flow.
Static electricity is potential energy. It does not move. It is stored.
For ex, when u rub a balloon
STATIC ELECTRICITY

Static…
Everything abt static…

Two oppositely charged objects will stick together
Often happens when clothes rub together in a tumble dryer
GROUNDING – occurs when a conductor shares its excess charge with a much
larger conductor
Static cling is…

Static Discharge…
Occurs when there is a loss of static electricity due to three possible things:
Friction - rubbing
Conduction – direct contact
Induction – through an electrical field (not direct contact)
In simple words, it’s a “shock” when u touch a door handle u might feel a “
shock” when u touch it, and that’s what u also call a “ Static Discharge ”

Currents

The passage of electrons over a wire is known as electric current.
And
The flow of electrons from one place to another.
We can control currents by circuits ( a path for the flow of electrons.We use wires. )
CURRENT IS
Types of currents
Direct Current (DC) – Where electrons flow in the same direction in a wire.
Alternating Current (AC) – electrons flow in different directions in a wire.

Conductors vs. Insulators

Insulators
Conductors
Material through which
electric current flows
easily.
materials through which
electric current cannot
move.

Insulators
Conductors
● Metal
● Water
● Styrofoam
● Rubber
● Plastic
● Paper

What is Resistance?
● The opposition to the flow of an electric current, producing heat.
● The greater the resistance, the less current gets through.
● Good conductors have low resistance.
● Measured in ohms.
What Influences Resistance?
● Material of wire – aluminum and copper have low resistance
● Thickness – the thicker the wire the lower the resistance
● Length – shorter wire has lower resistance
● Temperature – lower temperature has lower resistance.

Voltage

What is voltage?
● The measure of energy given to the charge flowing in a circuit.
● The greater the voltage, the greater the force or “pressure” that
drives the charge through the circuit.

For ex
● Amps measure how much water comes out of a hose.
● Volts measure how hard the water comes out of a hose.
Diff between these 2

Resistance = Voltage / Current
Ohms = Volts / Amps
Ohm’s law
“ / ”means “divide”

Circuits

Series Circuit: the components are lined up along one path. If the
circuit is broken, all components turn off.
Parallel Circuit : there are several branching paths to the components.
If the circuit is broken at any one branch, only the components on that
branch will turn off.
Types of circuits

Circuits
Series
Parallel

Umm i forgot what
u call it but it was
in the mock test

READ!!!
https://drive.google.c
om/file/d/1-xNtq8mK
1N4YsPuaSaoiPc0P
kGA0zd4D/view

Earth and
space
^_^

How was solar system formed ?
The Solar System is about 4,600 million years old. It was formed from a
nebula – an enormous cloud of dust and gas created when a dying star
exploded.
When shockwaves from other dying stars hit the nebula, it collapsed and
formed a globule.
Over millions of years, the temperature rose and the globule became
more compressed, causing it to start spinning.

How was solar system formed ?
● The force of the spinning shaped the globule into a central core
surrounded by a disk of gas and dust.
● Eventually, the core became the Sun and the material in the disk
formed
the planets and asteroids of the Solar System.

What makes up the Solar System?
● The sun
● The planets
● Moons
● Asteroids
● Comets

The sun
:0

The sun
●
● The Sun is the star at the centre of
the Solar System, about 150 million
kilometres from Earth.
● The Sun mostly consists of
hydrogen and helium.
● Its mass accounts for more
than 99% of the total mass of
the Solar System.

The sun
●
It is now known that nuclear fusion is
the process that releases the Sun’s
energy
He + energy

The planets

The
planets

Asteroids

The
asteroids

Comets

What are comets?
● The planets travel around the Sun in near-circular orbits. Comets are celestial objects
that also travel around the Sun, but in very elliptical orbits.
● The head of a comet is a lump of ice and dust, a few kilometres in diameter.
● For most of its orbit, a comet is a long way from the Sun. The tail of the comet only
appears when the its orbit passes nearest the Sun.
● The tail consists of gas and dust that are released from the comet by the heat of the Sun.

What are comets?

Stars

What powers a star?
● A star is ‘powered’ by nuclear fusion reactions taking place in its core.
● Nuclear fusion involves light atomic nuclei joining together (fusing) to form heavier ones.
● It would take 2,000 million nuclear power plants a whole year to produce the same amount
of energy on Earth.
● In the Sun and most stars, hydrogen atoms fuse together to form helium. This provides
the energy for life on Earth.

THE BIG BANG THEORY

WHat is the big bang theory
● The observation of red-shift is a key piece of evidence for the Big Bang theory about the
origin of the Universe.
● This states that the Universe ‘began’ with a colossal explosion 13,700 million years ago and
has been expanding ever since.
● The other key piece of evidence for the Big Bang theory is cosmic microwave background
radiation (CMB).
● CMB is radiation remaining from the Big Bang explosion and fills the whole of the universe.

Big bang theory

Summary
● black hole – An object whose gravitational pull is so strong that nothing can escape, not
even light. It is formed after a really massive star collapses in a supernova.
● comet – A lump of rock and ice, which has a very elliptical orbit around the Sun.
● Doppler effect – The shift in frequency of a sound wave or an electromagnetic wave due to
the relative movement of the source or observer.
● galaxy – A vast collection of millions of stars.
● nebula – A massive cloud of gas and dust in which a star
is formed.
● neutron star – The very dense core that remains after a massive red giant collapses in a
supernova.

Summary
● nuclear fusion – The process in which lighter atomic nuclei join together to make heavier
atomic nuclei and a massive amount of energy is released.
● red giant – The huge red star formed when a star expands and shines less brightly as it
starts to die.
● red shift – A shift in the wavelength of light towards the red end of the spectrum. It occurs
when the light source is moving away from the observer and is evidence for an expanding
Universe.
● supernova – The huge explosion that occurs when a massive red giant is at the end of its
life.
● white dwarf – The core that remains after the outer layers of a small red giant drift away.

Ques and ans that might be in the exam
1. What two elements make up most of the Sun?
hydrogen and helium
A huge cloud of gas and dust from which a star is born.
2. What is a nebula?
nuclear fusion
3. What process has allowed the Sun to emit light and heat energy over thousands of million of years?
neutron star
4. Which is the most dense, a white dwarf or a neutron star?

Seasons

● Most places on earth experience four
seasons---winter, spring, summer and fall or
autumn.the season always occur in order. Each season
seasons always occur in this order. Each season has its
own characteristics.
● As Earth revolves around the Sun, sunlight strikes
different parts of Earth at different angles. These
changes in the angle of the sunlight cause the seasons.
Seasons

Winter
● Winter is cold. The days are short and the nights are long. The sun does not rise very high
in the sky.
● Winter south of the ecuador, summer north of equator. The suns shines directly on the
Northern Hemisphere and indirectly in Southern Hemisphere

Summer
● Summer is the opposite. The days are longer than the nights, and the sun is high in the
sky.
● Summer south of the ecuador, winter north of equator. The suns shines directly on the
Southern Hemisphere and indirectly in Northern Hemisphere

Spring and fall
● On one day in spring and one day in fall, the amount of daytime and the amount of
nighttime are equal. There is 12 hours of each. These days are called the spring
equinox and the fall equinox.
● Spring south of the equator, fall north of the equator. The Sun shines equally on the
Southern and Northern Hemisphere
● Fall south of the equator, spring north of the equator. The Sun shines equally on the
Southern and Northern Hemisphere

Summer
Winter
Spring
Fall

Tides

● This animation shows the tidal force in a view of Earth
from the North Pole. As regions of Earth pass through
the bulges, they can experiences a high tide.

Tides
● Tides are a phenomenon on Earth that occurs in the pattern that
can be predicted.
● It is the rising and falling of sea levels everyday.
● Tides are caused by the pull of gravity – mostly from the moon.
The moon’s gravity pulls water away from the Earth’s surface. This
causes the water to rise, forming a bulge of water in the oceans.
● On the opposite side of Earth (away from the moon), the water is
also pulled away from Earth’s surface forming another bulge.
These bulges form high tides. The part of Earth closest to the
moon usually has the highest tides.

Low Tides
Low tides occur where
the water has been
pulled away. The Sun’s
gravity also influences
the tides, but the moon
has a greater effect
than the Sun because
the moon is so much
closer to the Earth.

High tide
High tides occur when the water reaches
its highest level in a day

Why does it happen
The main cause of tides is the pull of the Moon’s
gravity on Earth. The pull is greatest on whatever is
closest to the Moon. Although the gravity pulls the
land, only the water can move.

As a result
● Water on the side of Earth facing the Moon is pulled hardest by the Moon’s gravity. This
causes a bulge of water on that side of Earth. That bulge is a high tide.
● Earth itself is pulled harder by the Moon’s gravity than is the ocean on the side of Earth
opposite the Moon. As a result, there is bulge of water on the opposite side of Earth. This
creates another high tide.
● With water bulging on two sides of Earth, there’s less water left in between. This creates
low tides on the other two sides of the planet.

Spring tide
● occur during the new moon and full moon. The Sun and
Moon must either be in a straight line on the same side
of Earth, or they must be on opposite sides of Earth.
Their gravitational pull combines to cause very high
and very low tides.

Neap tide
● occur during the first and third quarters of the Moon. The
Moon and Sun are at right angles to each other. Their
gravity pulls on the oceans in different directions so the
highs and lows are not as great.

Layers of the
Earth and Rock &
Soil

The crust
The crust is made of relatively light elements, especially silica,
aluminum and oxygen.

The mantel
The upper part of the mantle nearest the crust
is solid and rigid, or stiff. Together, the crust
and the rigid part of the mantle makes up the
lithosphere.

Outer core
The outer core is the molten, fluid part of the core that is about 2,400 km
(1,500 mi) thick. The outer core is the third layer of the Earth. It is the
only liquid layer, and is mainly made up of the metals iron and nickel, as
well as small amounts of other substances. The outer core is responsible for
Earth's magnetic fieldIt is mostly composed of liquid iron and nickel.
.

Inner core
The inner core is solid. It is extremely dense, and is under a very high pressure.
It is about three-quarters big that of the moon. Extremely dense, it’s made mostly of iron
and nickel in solid form.The inner core spins a bit faster than the rest of the planet. It’s
also intensely hot: Temperatures sizzle at 5,400° Celsius (9,800° Fahrenheit). That’s almost
as hot as the surface of the sun.

Rock and
rock cycle
eee

Rocks
Rocks are classified by how they are formed
Igneous
Sedimentary
Metamorphic
Rocks can change from one type to another over time
Rocks are classified by:
How they are formed
Texture
Grain size
Mineral composition

Igneous Rocks
forms when molten rock
(magma) cools and hardens
Classified by:
Where they form
Crystal (grain) size
Igneous rocks (from the Latin
word for fire) form when hot,
molten rock crystallizes and
solidifies.

• Sedimentary rock:
Sedimentary rock: forms from the compaction
and/or cementation of sediments
This process is called lithification
Sediments are:
Rock pieces
Mineral grains
Shell fragments

Sedimentary rocks
● Sediments form through the processes of weathering and erosion of rocks exposed at
Earth’s surface. Sedimentary rock can also form from the chemical depositing of
materials that were once dissolved in water
● When water evaporates, minerals are left behind and form rock

Metamorphic Rock
● Metamorphic rock: forms when any rock type is changed
into a different kind of rock
● Changes due to great heat and/or pressure

Rocks are heated,
squeezed, folded, or
chemically changed by
contact with hot fluids

Rock cycle

The earth recycle rock
• The rock cycle is an ongoing series of processes
inside Earth and on the surface
• Slowly changes rocks from one kind to another
• Any type of rock can change into another type

Some pics

Earthquake

Earthquake is
● Earthquakes are the SHAKING, ROLLING or SUDDEN SHOCK of the earth’s surface.
● Earthquakes usually last less than one minute.
● They are the Earth’ natural means of releasing stress.
What causes earthquakes?
● Movement of TECTONIC PLATES or by the movement of magma in VOLCANIC areas.

Tectonic

Alfred wegerer
● In Wegener’s time many
people rejected the idea of
continental drift.
● However, new evidence supporting
Wegener's proposal came to light
in 1950’s. it became the basis of
Modern day tectonic theory.

3 types of plate tectonic
boundaries
● Convergent boundaries
● Transform boundaries
● Divergent boundaries

Convergent boundary
a convergent boundary occurs when two tectonic plates push
together.

Divergent boundary
occurs when two plates are spreading apart, as at seafloor ridges or
continental rift. Molten rock rises from the Earth’s center to fill the
gap.

Transform boundary
mark slip-sliding plates, such as California's San Andreas fault. The San
Andreas fault marks the location where the North America and Pacific
plates grind past each other in a horizontal motion.

How do earthquake
happen?
One plate will dive under the other
plate. This creates which we called
subduction zones.

Thank you!
&
Good luck!! <3