### Earth Surface & Energy Force – Physics

This Physics chapter covers earth surface and energy force.

displacement

distance and direction of a body’s position

velocity

speed of an object and direction of motion (vector)

acceleration

change in speed or direction per unit time

inertia

tendency of a body to resist changes in motion

force

push or pull between bodies

balanced forces

forces on one body have equal size but opposite direction

instantaneous speed

speed at a single point in time

friction

force that opposes motion between two touching surfaces

gravity

force of attraction between any two bodies

momentum

product of mass and velocity

static friction

force keeping two unmoving objects from moving past each other

weight

the gravitational force exerted on a body

chemical potential energy

energy stored in bonds between atoms

gravitational potential energy

energy of position (height)

joule

SI unit of energy

kinetic energy

energy of motion

mechanical energy

sum of PE and KE in a system

elastic potential energy

potential energy stored in an object that stretches or compresses

heat

thermal energy that moves from hot areas to cold areas

convection

heat transfer by movement of particles in a fluid

conduction

heat transfer by touch

heat engine

device that converts heat energy to mechanical energy

temperature

average kinetic energy of particles in a material

heat mover

device that removes thermal energy from one location and transfers it to another location at a different temperature (ex. air conditioner)

Joule

the unit for work is the:

Newton

the unit for force is the:

power

the rate at which work is done ( work/ time )

machine

a device that allows you to do work in a way that is easier

the number of times a machine increases a force exerted on it ( output force/ input force )

1st class lever

What class lever is this? effort———-load

^Ex: see saw, scissors, oar

2nd class lever

What class lever is this? effort—-load——
^
Ex: bottle opener, wheelbarrow

3rd class lever

What class lever is this? load—-effort—–
e ^
Ex: rake, fishing rod, tweezers

inclined plane

a flat, sloped surface that acts as a simple machine

wedge

a device that is thick at one end and tapers to a thin edge at the other end

screw

an inclined plane wrapped around a cylinder

lever

a rigid bar that is free to pivot or rotate on a fixed point

fulcrum

the fixed point on which a lever is free to pivot or rotate

wheel and axle

a simple machine made of two cylindrical objects fastened together that rotate around a common axis

pulley

a simple machine made of a grooved wheel with a rope or cable around it

fixed pulley

the type of pulley that requires more effort than the load to lift the load from the ground, does not need to be pushed or pulled up or down

movable pulley

a type of pulley that moves with the load and allows the effort to be less than the weight of the load

compound machine

a machine that utilizes two or more simple machines

doppler effect

the change in frequenct of a wave as its source moves in relation to an observer

dry cell

an electrochemical cell in which the electrolyte is a paste

wet cell

an electrochemical cell in which the electrolyte is a liquid

potential energy

stored energy that results from the position or shape of an object

parallel circuit

an electric circuit with multiple paths

kinetic energy

energy that an object has due to its motion

temperature

speed of sound depends on the type of medium as well as its _______________.

light

which is faster, light or sound?

reflects

the color of an opaque object is the color of the light it _________.

magenta

red light + blue light =

cyan

blue light + green light =

yellow

red light + green light =

red

magenta pigment + yellow pigment =

green

yellow pigment + cyan pigment =

blue

magenta pigment + cyan pigment =

light

when the electron calls back a photon is given off, creating this:

solar energy

energy from the sun

specific heat

measure of energy needed to raise the temperature of an object (water: 4.184 J/(kg K))

transfer of energy by electromagnetic waves

thermal energy

total kinetic and potential energy of all the particles in a substance

interference

combination of two overlapping waves

refraction

the bending of a wave as it changes speed between mediums

wavelength

distance between crests on a transverse wave

medium

the matter a wave travels through

transverse wave

a wave in which matter moves at right angles to the wave direction

What are the earliest forms of life on Earth

Single Cell Organisms (bacteria) that evolved from the “Primordial Soup” in the depths of the oceans

When did the cyanobacteria form?

3.5 billion years ago

Cyanobacteria group together to form major structures called what

Stromatolites

Cyanobacteria use the sun’s energy to do what

Photosynthesize (make there own food)

evolution

The gradual change of characteristics within a population, producing a change in species over time

natural selection

process that drives evolution by charles darwin who wrote the origin of species

Modern synthesis

concept that evolution was a process of gradual adaptive change in traits among populations

Gene pool

the entire collection of genes within a given population

mutation

a change of the DNA sequence of a gene

genetic drift

recognized to influence the evolution of new traits. a small change in frequency of particular genes simply due to chance influence.

gene migration

the introduction of new genes from the immigrant results in a change of the gene pool

Hardy-Weinber Law of Equilibrium

study of genetics shows that in a situation where random mating is ocurring within a population: formula is p2+2pq+q2=1

When was our sun formed

4.6 billion years ago

Where did the dust and rock come from that formed our Earth

Formation of the sun

How old is our Earth

4.5 billion years old

There was air on Earth at its beginning

False

What elements/compounds were present on Earth at this time

Iron, nickel, and carbon

What was Earth like at its birth

It was a hot ball of magma on the surface and had an iron and nickel core in the center

What planet collided with Earth

Thea

Both planets turned into

Magma (rocks)

How was the moon formed

From left over debris from the Earth’s collision with Thea

How close was the Earth was the Moon when it was formed? How far is it from Earth today?

It was very close and has moved farther away

At this point how long does a day on the Earth last

6 hours

How did water end up on Earth

In crystals that were in meteors from space

At this point in time the Earth has cooled down enough to allow what to form on its surface

Crust

What affect did the young moon have on Earth

It created violent storms in the ocean because of its gravitational force

What formed on the surface of Earth

Volcanos

What did the Volcanos allow to emerge from the oceans

Volcanic islands

What gas mostly made up the atmosphere of the young Earth

Carbon Dioxide

Meteors again bombarded the Earth, dissolve and bring what from outer space

Minerals and heavy elements

Stromatolites release what gas into the ocean?

Oxygen

How did oxygen get into our atmosphere?

Dissolved oxygen in the ocean rose to the surface and dissipated (spread out) into Earth’s atmosphere

What was the name of the super continent?

Rowdinia

What is the driving force that splits the super continent?

Heat from inside the Earth

Why isn’t the sun’s heat trapped inside the planet’s atmosphere?

There is no carbon dioxide to trap the sun’s radiation (heat)

What is the nickname of Earth during this ice age?

Snow Ball Earth – the longest and coldest ice age of Earth’s history

What releases the Earth from this very long frozen period?

Volcanic activity

What oxygen-rich chemical does the chemical reaction between ultraviolet light and ice make?

Hydrogen Peroxide – released large amounts of oxygen

What did primitive bacteria evolve into?

Multicellular Bacteria (trilobites)

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