Kategorier: Alle - gravity - stability

af C Daniel 5 måneder siden

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PAT review

Bernoulli's Principle explains how varying air speeds around an object create different pressures, fundamental to aerodynamics. Faster air movement results in low pressure, whereas slower air results in high pressure.

PAT review

PAT review

crime and investigation

Fabric Analysis
Texture
Reaction to heat
Color
Absorbency
Stretchability
Handwriting Analysis
Content – Spelling, punctuation, and grammar
Arrangement – The spacing of the letters across the page
Lines – thickness of the lines made by the pen or pencil
Form – the slant, shape, and curves of the letters
Chromatography
chromatography is a method that is used to separate colored chemicals or substances, such as the ink in pens.
Fingerprints
Everyone has their own unique fingerprint.
Footprints
Height

A person’s height can be estimated by using the size of the footprint.

Weight

Scientists use weights on the same ground to estimate weight of person.

The deeper the footprint, the heavier the person was.

Speed

The wide the space, the faster the person was moving.

Short spaced footprints show a slow walk

E.g. Speed, Direction, Weight, Height, Where the person has been
Footprints can tell you a lot of information about an individual.
Observation Skills
Looking for Signs/Clues

Every activity leaves behind a trail of clues or signs of what happened.

To find clues, one must learn to observe correctly.
Observation: the action or process of observing something or someone carefully in order to gain information.
There are 2 problems when it comes to Evidence
Determining what the clues mean or DEDUCING (Deduction)
Finding the clues.

sky science

Heavenly Bodies
meteorites

Meteors that reach the Earth’s surface in solid form.

meteors

Are merorites that have entered earths atmosphere and burn up.

`They are called shooting stars as they fall toward the Earth.

meteo`roids

They are attracted to Earth by Earth’s gravity.

`Meteoroids are small, solid bodies from outer space.

asteroids

They are found mostly between Mars and Jupiter.

They travel in elliptical orbits around the sun, just like planets.

Asteroids are mini planets.

Comets

They often have a “tail.”

They travel in elliptical orbits around the sun.

Comets are made up of mostly dirt and ice.

Moons

Earth’s moon is visible because it reflects light from the Sun.

Some planets have no moons, while some planets have many.

Moons are the natural satellites of planets.

The Planets

The planets reflect light from the Sun.

Each planet varies in size, appearance, and composition.

The planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

There are 8 planets that revolve around the Sun.

The Sun

Without the sun there could be no life on Earth.

The sun emits light and gives off heat.

The word solar means sun.

The Sun is the star that is at the center of our solar system.

constellations

The Big Dipper (Ursa Major), and Orion are all constellations.

There are 88 constellations in the sky.

A constellation is a group of stars that appears to form a pattern in the sky.

galaxies

Approximately 200 million stars are in the Milky Way. The Sun is one of them.

Our galaxy is called The Milky Way.

A galaxy is a cluster of stars.

The closest star to the Earth is the Sun.

They emit light through nuclear fusion, which happens deep inside the star.

They come in all shapes, sizes, colours, compositions, and temperatures.

Stars are the heat and light sources of the universe.

satellites

Humans have launched man-made satellites so that they orbit the Earth.

The planets are natural satellites of the Sun.

The moon is a natural satellite for the planet Earth.

A satellite is the name for any heavenly body that revolves around another.

galaxys an stars and plants
reflect

planets

give back or bounce

emit

stars

give off

Solar System

There are eight planets that make up our solar system

Neptune

Uranus

Jupiter

Mars

Earth

Venus

Mercury

Galaxy

You can see the andromeda galaxy in the sky

The closest galaxy to earth is the Andromeda Galaxy which is 2 million light years away

The Milky way galaxy contains 200 billion stars

Earth is a part of the milky way galaxy

The Universe

Space is also filled with radiation (e.g. light and heat), magnetic fields and high energy particles (e.g. cosmic rays).

The space between the stars and galaxies is largely empty but contains some scattered particles of dust or a few hydrogen atoms per cubic centimeter.

Contains billions of galaxies, each containing millions or billions of stars.

Properties of Air

Airplanes & Controlling FlightAirplanes & Controlling Flight
Rudders: Yaw

The rudder is located on the tail of the aircraft. It works identically to a rudder on a boat, steering the nose of the aircraft left and right. Unlike the boat however, it is not the primary method of steering. Its main purpose is to counteract the drag caused by the lowered aileron during a turn. This adverse yaw, as it is known, causes the nose of the airplane to point away, or outwards, from the direction of the turn. The rudder helps to correct this by pushing the nose in the correct direction, maintaining what is known as coordinated flight

Ailerons: Roll

The ailerons are located at the rear of the wing, one on each side. They work opposite to each other, so when one is raised, the other is lowered. Their job is to increase the lift on one wing, while reducing the lift on the other. By doing this, they roll the aircraft sideways, which allows the aircraft to turn. This is the primary method of steering a fixed-wing aircraft.

Elevators: Pitch

As the name implies, the elevator helps “elevate” the aircraft. It is usually located on the tail of the aircraft and serves two purposes. The first is to provide stability by producing a downward force on the tail. Airplanes are traditionally nose-heavy and this downward force is required to compensate for that. The second is to direct the nose of the aircraft either upwards or downwards, known as pitch, in order to make the airplane climb and descend.

Rudder/Vertical and Horizontal Stabilizers

When the elevator is lowered, the nose drops

When angled up, the nose of the plane rises

The elevator can be controlled in an up and down motion

The horizontal stabilizer prevents an up-and-down motion of the nose, which is called pitch.

The vertical stabilizer keeps the nose of the plane from swinging from side to side, which is called yaw. Motion can be controlled by the rudder.

The stabilizers’ job is to provide stability for the aircraft, to keep it flying straight.

To control and maneuver the aircraft, smaller wings are located at the tail of the plane.

Aileron

Ex. If the left aileron is lowered and the right aileron is raised, the plane will roll to the right

If they are angled in opposite directions, the plane will roll in the direction of the raised aileron

Ailerons are small surfaces on the ends of the wings

Slats/Spoiler (located on wings)

Slats are used at takeoff and landing to produce additional force. The spoilers are also used during landing to slow the plane down and to counteract the flaps when the aircraft is on the ground.

Flaps are deployed downward on takeoff and landing to increase the amount of force produced by the wing. On some aircraft, the front part of the wing will also deflect.

Turbines/Jet Engines & Propellers

Smaller, low-speed airplanes use propellers for the propulsion system instead of turbine engines.

The turbine engines, which are located beneath the wings, provide the thrust to overcome drag and push the airplane forward through the air.

Wings/Airfoil

Modern airliners use winglets on the tips of the wings to reduce drag.

The wings generate most of the lift to hold the plane in the air.

To generate lift, the airplane must be pushed through the air. The air resists the motion in the form of aerodynamic drag.

Cockpit

It has all the controls to fly the plane

The front part of the aircraft where the pilots fly the plane from

Fuselage

It can be used to carry passengers and cargo

It is a long, hollow tube that holds all of the pieces of an airplane together

The fuselage is the main body of the airplane

5 Propertys
Property 5: Air is Affected by Temperature

The colder the air becomes, the slower the air particles move (lowering pressure)

The greater the temperature, the faster the air particles move (increasing pressure)

Property 4: Air can be Compressed

Air particles can be compressed and squished together to take up less space.

Property 3: Air Exerts Pressure

Air exerts pressure (in all directions). The air above the paper pushes down on it (pressure). This pressure is what makes the paper lay flat on the table - it's being pushed down. Even though they're too tiny to see, all the molecules of air in the atmosphere above your head weigh something.

Property 2: Air Has Mass

Every square inch of surface on the earth has about 15 pounds of air sitting on it. Air is piled about 100 miles high on each square inch.

Air is really quite heavy and has mass. You don’t notice it because your body is adapted withstand the air pressure that you experience every day.

Property 1: Air Takes Up Space

Air is a mixture of gasses that take up space in the world around you. Although you may not see it or think because it has always been there, air takes up the space around us.

WHAT ADAPTATIONS DO INSECTS have to help them FLY
Insects don’t have bones - their bodies are light
Strong muscles in the midsection or thorax
Wings don’t just flap up and down, they rotate
Wings are shaped like an airfoil, just like birds and airplanes
Wings are very light structures
Most insects have two pairs of wings
Bernoulli’s Principle
Faster air = low pressure Slower air = high pressure
Bernoulli’s Principle: as air moves around an object, it creates different pressures on that object
Daniel Bernoulli was a Swiss mathematician and physicist He came from a family of mathematicians He helped create Bernoulli’s Principle, which is very important in Aerodynamics
Forces of Flight
lift

Lift occurs as a result of the shape of an airplane’s wing *Bernoulli’s Principle *

Lift holds an airplane up in the sky

Lift pushes upward, allowing a plane to fly

Parachutes
When you first release the parachute, the force of gravity pulls it downward, and the parachute speeds toward the ground. The faster the parachute falls, though, the more drag it creates. The drag force resists the downward movement of gravity, pushing the parachute back up.

trees and forests

Tree and Leaf Classification
Leaf Classification

vein - Vascular structure on a leaf. Provides support for the leaf and transport of both water and food.

petiole - a leaf stalk; it attaches the leaf to the plant.

midrib - the central rib of a leaf - it is usually continuous with the petiole.

leaf apex - the outer end of a leaf; the end that is opposite the petiole.

Classifying Tree Species

Leaves

Bark

Branching Patterns

Branch location

Silhouette

Type (deciduous vs coniferous)

Growing conditions
Infestation

When trees are infested by insects or disease, it can leave holes or scars within the tree.

Fire scars

This can lead to a fire scar and irregular growth of the tree around the scar.

Trees sometimes lose part of their trunk due to a forest fire.

Competition, Pushing, and Slope

Sometimes you may notice a ring with wider growth on one side and narrower growth on the other.

Trees growing on an uneven slope (hillside or uneven ground)

Trees pushing up against a building

Competition from other nearby trees

Drought

You know a tree has gone through a drought when some rings are narrower than others

Tree rings can be narrower in sections because the tree has not had access to enough water which slows its growth

Optimal Growing Conditions

You know the tree has had optimal growing conditions if all tree rings are the same size

Tree is able to grow effectively without any interruptions in its cycle due to environmental conditions

What are the different parts of a Tree
Item 6 Outer Bark

This layer protects a tree from insects and disease, excessive heat and cold, and other injuries.

Item 5 Heartwood

Heartwood develops as a tree gets older. It is old sapwood that no longer carries sap, and gives the trunk support and stiffness. In many kinds of trees, heartwood is a darker color than sapwood, since its water-carrying tubes get clogged up. The tree cookie at right, like many of its fellow young pines, has not developed heartwood yet.

Item 4 Growth Ring

The lighter portion is called the "early wood" (beacuse it grows in the spring), and the darker portion the "late wood" (which grows in the summer). Together, they represent one year of growth.

Item 3 Xylem

Also called the sapwood. This layer carries the sap (water plus nitrogen and mineral nutrients) back up from the roots to the leaves. Sapwood gives a tree its strength.

Item 2 Phloem

Also called the inner bark. This layer carries sugar made in the leaves or needles down to the branches trunks and roots, where it is converted into the food the tree needs for growth.

Item 1 Cambium

The layer or zone of cells, just one cell thick, inside the inner bark. The cambium produces both the xylem and phloem cells. This is where diameter growth occurs, and where rings and inner bark are formed.

Tree Cookies
tree rings

Together these two types of wood represent one year of growth

Late wood: dark colored and is the growth that happens over fall and winter

Early Wood: Light colored wood is called early wood as it grows in summer and spring

Every year a tree is alive is adds new growth to its trunk that when analyzed can help you to understand more information about the tree

Tree rings are like the growth chart of a tree. Easily visible rings can provide information about the weather, soil, and light conditions over time.
Dendrochronology

A dendrodisc (tree cookie) is a cross sectional slice of a tree.

Dendrochronology is the scientific study of growth patterns and the aging of trees, as shown in their rings.

Dendrochronology comes from the roots dendro- meaning “tree” and chronology meaning “the study of time.”

what is a tree
A plant with supporting woody branches and leaves
A plant with a long woody stem known as a trunk
A perennial - this means a plant with a continuous growth cycle
type of trees
Deciduous

From the Latin word decider – “fall down or off”

Have existed for 60 – 100 million years

Seeds are in vessels – fruit, capsules, seeds, etc.

Do not withstand temperature extremes

Are broad-leafed

Shed leaves in fall, grow leaves in spring

known as “broadleaved trees” or “hardwoods trees”

Coniferous

facts

From the Latin word conifer – “cone-bearing”

Have existed for about 300 million years

Seeds are well protected by a sharp-toothed cone

Are good at withstanding temperature extremes

Stay green all year round

Have needle shaped leaves

Shed and grow their leaves continually.

known as “evergreens” or “softwoods ”