Organ System & Law Of Motion – Biology
This chapter covers organ system and law of motion of biology.
mesoderm
later turns into muscles and organs of the skeletal system etc.
germ layers
when this develops the embryo is visible
extraembryonic membranes
membranes not part of the emryos themselves
umbilical cord
contains blood vessels which exchanges gases from its mother
chorioallantoic membrane
regulates gas exchange through the shell which forms witht the chorion
placenta
the connection between the mother and embryo
inheritance
process by which characteristics pass form one generation to another
gregor mendel
man who studied the principles of heredity/genetics
p1 generation
first generation of true breeding
f1 generation
first generation of offspring
genes
heredity factors
chromosomes
carry all the genetic information in most organisms
homologous chromosomes
corresponding pairs of chromosomes
locus
genes that produce a given trait exist at the same position
alleles
individual chromosomes
genotype
combination of alleles
phenotype
the expressed type of a genotype
dominant
if it masks the effect of its partner allele
recessive
the allele that does not produce its trait when present with a dominant allele
punnett square
a chart that allows us to easily predict the results of genetic cross.
homozygous
when both alleles for a given gene are the same
heterozygous
when they are different
monohybrid
a cross between two individuals where only one trait is considered
dihybrid cross
crossing two parents while considering two separate traits
law of segregation
states that traits are expressed from a pair of genes in the individual.
law of dominance
when one gene was usually dominant over the other
law of independent assortment
the separation of alleles and making the independently sorted
imcomplete dominance
example of a white flower and a red flower making it pink. neither was dominant
linked
traits that are linked together
crossing over
random breaking and reforming of homologous chromosomes allow genes to change the chromosome they are linked to. adds more possibility of variation of traits among species
polygenic traits
traits produced from interaction of multiple sets of genes
chapter 5
ecology and population biology
ecology
the study of how organisms interact with other organisms
environment
are where organisms are influenced. their physical environment
ecosystem
a group of populations found within a given locality
population
the total number of a single species or organism found in a given ecosystem
organism
and individual of a particular species
community
populations that interact with each other in a particular ecosystem
biosphere
the part of the earth that includes all living things
atmosphere
area that includes air ground and water
lithosphere
the ground
hydrosphere
water
habitat
the physical place where a species lives
biotic
factors that support life such as living things food source, and predators
abiotic
nonliving things in the habitat-weather temperature, soil
niche
the role a species plays within the ecosystem
energy cycle
life supported throughout the environment
biogeochemical cycles
the water cycle, the carbon cycle, the nitrogen cycle, the phosphorous cycle
energy cycles
cycles within the ecosystem
food chain
the cycle where energy flows to producers, consumer, to decomposer
carnivores
animals that feed on other animals
omnivores
animals that consume photosyntheic organisms and other animals
trophic levels
steps in the food chain
fossil fuels
organic matter that is left to decay under conditions of heat
natality
overall growth rate or birth rate
mortality
death rate
abiotic factors
factors that affect the environment with an ecosystem-physical and non living factors such as fires pollution and sunlight
biotic factors
biological factors including availability of food, competition, predator-prey relationships, symbiosis, and overpopulation
limiting factors
this is what determines how much a particular poplation within a community will be able to grow
homeostasis
the dynamic balance achieved within an ecosystem functioning at its optimum level
density
number of organism per area
density independent factors
abiotic limiting factors-that is, they are independent of population density
density-dependent factors
population growth issues and interactions between species within a community
carrying capacity
maximum level the population may reach
range
area occupied by a species of a particular geographic area
dispersion
over time, species may move in or out of a particular area
emigration
permanent one way movement out of the original range
immigration
permanent one way movement into a new range
migration
temporary movement out of one range into another and back
competition
when two or more species live within the same area and that overlap niches
competitive exclusion
when a species is wiped out in an area due to competition
predator
an organism that eats another
prey
the organism that is eaten
symbiosis
when two species interact with each other within the same range
amensalism
type of symbiosis where one species is neither helped nor harmed while it inhibits the growth of another species
mutualism
form of symbiosis where both species benefit
parasitism
symbiosis in which one species benefits but the other is harmed
extinction
when the entire population of a particular species is eliminated
minimal viable population
when a population becomes susceptible to breeding problems that may result to extinction
community structure
characteristics of a specified community including the types of species that are dominant
closed communit
one whose populations occupy essentiall the same range with very similar distributions of density
ecotones
boundaries such as a pond
open community
indefinite boundaries
succession
when one community completely replaces another over time in a given area
pioneer communities
first population that moves back into a disturbed ecosystem
climax community
when succession ends in a stable community
biome
an ecosystem that is generally defined by its climate characteristics
terrestrial biomes
biome that exists on land
aquatic biomes
large bodies of water
biogeography
the study of how photosynthetic organisms and animals are distributed in a particular location
dispersal
process how animals and organism arrive in a location
introduced
species that inhabit a given ecosystem because humans transported them there
native
new species that develop from parents that were dispersed there
ethology
study of how animals act and react within their environments
innate behaviors
actions in animals that are also called instincts
stereotyped behaviours
varieties of behaviors-taxes kineses, reflexes fixed action patterns
taxes
are directional responses either toward or away from a stimulus
kineses
changes in speed of movement in response to stimuli
reflexes
automatic movement of a body part in response to a stimulus
fixed action patter FAP
complex but stereotyped behaviors in response to a stimulus
releaser/sign stimulus
pre-programmed response to a particular stimulus
learned behaviors
behaviors that are learned. 3 types; conditoning, habituation, imprinting
conditioning
learning an old response to a new stimulus
habituation
behavior where the organism produces less and less response as a stimulus is repeated. without subsequent negative or positive reaction
imprintinng
behavior that develops in a critical or sensitive period of the animals life
social behavior
pattern that take into account other individuals
home range
an area where animals spend most of their time
territory
area where an individual will defend
sexual and mating patterns
behavior that relies on complex interactions of the endocrine, nervous, and musculoskeletal systems
society
an organization of individuals in a population in which tasks are divide, in order for the group to work together.
dominance
older more established individuals that compete for status within the community
altruism
traits that tend to serve the needs of the society as a whole in addition to its own individual needs
demographic transition
a theory that proposes there are progressive demographic time perios of human population growth
biomedical progress
within urban societies that causes a lowering of the infant mortality rate
age composition
the relative numbers of individuals of specific ages within the population
genetic engineering
the intentional alteration of genetic material of a living organism
envrionmental pollution
the addition of contaminants to the air and water by human intervention
covalent bond
bond when atoms share electrons
molecule
two or more atoms held together by shared electrons (covalent bonds).
compound
when two or more different atoms bond together chemically to fomr a unique substance.
ions
charged atoms
cation
when an atom loses one or more electrons becomes positively charged particle, or a positive ion.
anion
an atom that gains one or more electrons becomes negatively charged
ionic bond
strongest bond of a positive and negative ions that are attracted
polar molecules
molecules that have regions of partial charge
hydrogen bond
the force of attraction between water molecules (weak chemical bond).
van der waals forces
momentary forces of attraction that exist between molecules and are much weaker than the forces of chemical bonding.
polar intermolecular attraction
exist between two polar molecules that has a slightly positive endo of one molecule forms that forms an electrostatic attraction to the slightly negative end of another molecule.
hydrogen bond
when a hydrogen atom is involved with a polar intermolecular attraction to a more electronegative atom.
physical properties
relate to the forces between atoms and molecules. Hardness, melting point, and boiling points.
network covalent crystals
the strongest attraction holding atoms together. high melting point and hardest of all crystals
ionic crystals
strong electrostatic forces holding atoms together
nonpolar molecules
soft crystals that are easily deformed that are predominantly held together with van der waals forces
polar molecules
intermolecular attractions that are weaker than ionic forces but are much stronger than nonpolar dispersion forces.
reactants
reacting molecules
products
newly formed molecules
decomposition
the breakdown of a compound into its components
combination
the revers of decomposition
replacement
when a compound breaks apart and forms a new compound with a free reactant
endothermic reactions
reactions that require energy
exothermic
reactions that release energy
laws of thermodynamics
laws that chemical reactions are subject to
entropy
law of increasing disorder-asserts that all reactions spread energy, which tends to diminish its availability
acid
a chemical that donates protons when dissolved in water-the measure of concentration of H+ ions in a solution
base
a chemical that accepts protons when dissolved in water
pH scale
potentional of hydrogen-measurement of H+ ions in solution
organic compounds
the building blocks of all living things. compounds that contain carbon-hydrogen, oxygen, nitrogen.
carbohydrates
made up of varying combinations of only carbon, hydrogen, and oxygen.
sugars and starches
forms of carbohydrates
monosaccharide
the basic sugar unit
disacharide
two monosaccharide molecules that join together-table sugar
trisaccharide
when three monosaccharides join together
polysaccharide
when more than three monosaccharides merge
starches
starches are a plants energy which are stored in the plants cells
cellulose
a plant fiber that is a long chain of water insoluble polysaccharid
glycogen
a polysaccharides compose of many joined glucose units
lipids
organic compounds comosed of carbon, hydrogen, and oxygen. -waxes steroids phospholipids and fats
fats
efficient lipid molecules used for long-term energy storage.
proteins
large un-branched chains of amino acids
amino acids
single links (monomers) that join together to form linear chains with many links.
polymers
many links of amino acids
polypeptides
another name for proteins
enzymes
special proteins that act as catalysts for reactions
catalyst
a substance that changes the speed of a reaction without it being affected itself.
DNA
a form of nucleic acid.
double-helix
structure of DNA was discovered and modeled by two scientists
Watson Crick
the DNA and RNA structure is known as this
Heat
energy that flows from an object that is warm to an object that is cooler
temperature
the measure of the average kinetic energy of a substance
radiation
the transfer of energy via waves
convention
the movement of energy by the movement of matter, usually through currents.
conduction
movement of energy by transfer from particle to particle
specific heat
the measure of a substances’ ability to retain energy
law of conservation of matter and energy
first law says that matter and energy can neither be created nor destroyed
law of entropy
second law of thermodynamics states that whenever energy is exchanged, some energy becomes unavailable for use
law of absolute zero
third law of thermodynamics says that absolute zero cannot be attained in any system.
melting point
temperature at which a substance changes from solid to liquid form
heat of fusion
heat required to melt 1 kg of a solid at its melting point (also known as enthalpy of fusion).
freezing point
temperature at which a substance changes from liquid to solid
boiling point
temperature at which a substance changes from liquid to gas
heat of vaporization
amount of energy required to change 1kg of liquid of a substance to a gas (also known as enthalpy of vaporization)
evaporation
escape of individual particles of a substance into gaseous form
condensation
change of a gaseous substance to liquid form
diffusion
mixing of particles in a gas or liquid
density
the measure of how much matter exists in a given volume. D=m/v
electrons
electrical charges consist of theses gathered on the surface of an object
conductors
substances where electrical charges can move through
electrical current
a flow of electrons through a conductor
insulators
the opposite of conductor-poor conductors
circuit
the path that an electic current follows. has 4 parts; a source of voltage, set of conductors, a load, a switch
closed circuit
a circuit that has a continuous path for electron flow
open circuit
circuit that has no flow of electrons because the pathway is interrupted
voltage
the electromative force that pushes electrons through the circuit
amperage
the measure of the amount of electron flow or current
resistance
a hindrance to current due to objects that deter the current by their size, shape or type of conductor
magnetism
the ability of a substance to produce a magnetic field
transverse wave
a wave that causes particles to move up and down while the wave moves forward
longitudinal wave
wave where particles move back and forth but in the same direction as the wave motion
wavelength
the distance from one crest of a wave to the next crest on the same side
frequency
the number of wavelengths that pass a point in a second
interference
when two crests collide and cancel each other out
reflected
when wave collide and go the other way
diffraction
the bending of a light wave around an obstacle
reflection
the bouncing of a wave of light off an object
refraction
the change of direction of a wave as it passes from one medium to another.
light spectrum
the arrangement of components of a light wave according to wavelength
celestial mechanics
sophisticated mathematical relationship to clarify the movement of objects in the Milky Way
redshift
light spectrum of velocities of galaxies that indicated that galaxies are moving away from one another
mesosphere
the atomospheric layer found at approximately 50-80km altitude
mesopause
separates the stratosphere from the next layer the thermosphere
thermosphere
found at altitudes of approximately 80 to 480 kilometers
exosphere
960 to 1000 km
ionosphere
portions of the mesosphere and thermosphere
auroras
lights that come from electrons rejoin the atoms.
atomospheric pressure
the total weight of the atmosphere that is exerted on the earth
barometer
measurement of the atmospheric pressur
geosphere
the solid or mineral part of the earth
crust
the outermost layer of the geosphere
mantle
the complex middle layer of the geosphere.
core
the innermost layer of the geoshpere composed of mostly iron and nickel
lithosphere
the rigid outermost layer of the geosphere
asthenosphere
is the molten plastic outer mantl of hot silicate rock beneath the lithosphere
mohorovicic discontinuity/moho
the sharp boundary between the crust and mantle
gutenberg discontinuity
separates the mantl from the core
Physical Quantity
A quantity that can be measured and consists of a numerical magnitude and unit
Scalar quantity
Quantities that have magnitude only
Vector quantity
Quantities that have both magnitude and direction
Distance
Total length of travel disregarding the direction of motion
Displacement
Total length moved in a specific direction
Speed
Rate of change of distance
Velocity
Distance travelled per unit time in a specified direction OR Rate of change of displacement
Acceleration
Rate of change of velocity
Newton’s First Law of Motion
An object at rest will remain at rest and an object in motion will continue in motion at constant speed in a straight line in the absence of a resultant force acting on it
Newton’s Second Law of Motion
The resultant force acting upon an object is equal to the product of the mass and the acceleration of the object; the direction of the force is the same as that of the object’s acceleration
Newton’s Third Law of Motion
If an object A exerts a force on object B, then B exerts an equal but opposite force on A
Friction
Friction is a force that resists the relative motion of objects that are in contact with each other
Mass
Measure of the amount of substance in that object
Weight
Force of gravity acting upon that object
Gravitational Field
Region in which a mass experiences a force due to gravitational attraction
Gravitational Field Strength
Gravitational force per unit mass
Moment of a force (torque)
The product of force and perpendicular distance from the line of action of the force to the pivot
Principle of moments
When an object is in equilibrium, the sum of clockwise moments about any point is equal to the sum of anticlockwise moments about the same point
Centre of gravity
The point through which the entire weight of the object appears to act
Energy
Capacity to do work
Kinetic energy
Energy a body possesses due to its motion
Thermal energy
Total kinetic energy of the atoms or molecules in the body
Potential Energy
Energy stored in an object due to its position, state, or shape
Gravitational potential energy
Energy which an object possesses because of its position relative to the ground
Principle of conservation of energy
Energy cannot be created nor destroyed but only changes from one form to another. The total energy in an enclosed system remains constant
Power
Rate of doing work
Effiency
Ratio of the useful energy output to the total energy input
Brownian motion
Haphazard movement of microscopic particles suspended in a fluid due to the uneven bombardment of the suspended particles by the molecules of the fluid
Kinetic model of matter
All matter is made of a large number of tiny atoms or molecules which are in continuous motion
Internal Energy
Combination of the total kinetic energy and potential energy of the molecules in the body
Ice point
Temperature of pure melting ice at standard atmospheric pressure
Steam point
The temperature at which pure boiling water changes into steam at standard atmospheric pressure
Conduction
Process by which thermal energy is transmitted through a medium from one particle to another
Convection
Process by which thermal energy is transmitted from one place to another by the movement of heated gas or liquid
Radiation
Process by which thermal energy is transferred by electromagnetic waves
Heat capacity
Amount of thermal energy required to raise the temperature of the body by 1K or 1oC
Specific heat capacity
Amount of thermal energy required to raise the temperature of a unit mass of the substance by 1K or 1oC
Melting
Process whereby energy is supplied to change the state of a substance from solid to liquid, without a change in temperature
Freezing
Process of changing state of a substance from a liquid to a solid without a change in temperature
Boiling
Process whereby energy is supplied to change the state of a substance form liquid to gas, without a change in temperature
Condensation
Process of changing the state of a substance from gas to liquid without a change in temperature
Latent heat of fusion
Energy needed to change the state of a substance from solid to liquid, without a change in temperature
Latent heat of vaporisation
Energy needed to change the state of a substance from liquid to gas, without a change in temperature
Specific latent heat of fusion
Amount of thermal energy needed to change a unit mass of the substance from solid to liquid, without a change in temperature
Specific latent heat of vaporisation
Amount of thermal energy needed to change a unit mass of the substance from liquid to gas, without a change in temperature
Heat
energy that flows from an object that is warm to an object that is cooler.
Temperature
the measure of the average kinetic energy of a substance
Average kinetic energy
The energy of the motion of the atoms and molecules in a substance. The lower temperature, the slower particle motion (less energy); The higher the temperature, the faster the motion (more energy)
Absolute zero
The coldest temperature, 0 Kelvin, that can be reached. It is the hypothetical temperature at which all molecular motion stops.
Radiation
energy that is radiated or transmitted in the form of rays or waves or particles.
Convection
the movement of energy by the movement of matter, usually through currents. eg. convection moves warm air up, while cool air sinks. In a fluid, the heat will move with the fluid.
Conduction
the transfer of thermal energy from one substance to another through direct contact
specific heat
The measure of a substance’s ability to retain energy. The heat required to raise the temperature of one gram of a substance one degree centigrade.
Law of thermodynamics
the interaction between heat and work (energy) in the universe
Law of conservation of matter and energy
First law: matter and energy cannot be created or destroyed
Law of entropy
Second law: whenever energy is exchanged, some energy becomes unavailable for use (entropy increases)
Law of absolute zero
Third law: absolute zero cannot be attained in any system (that is energy of motion of particles cannot be stopped)
States of matter
solid, liquid, gas, plasma
Plasma
a state of matter that consists of free-moving ions and electrons; only exists in the case of extreme heat and ionization.
solid
A state of matter that has a definite shape and a definite volume; the molecules are packed and bonded together. the strength of the bonds determines the strength of the solid and its melting point
liquid
a substance in the fluid state of matter having no fixed shape but a fixed volume
gas
matter that does not have a definite shape or volume; has particles that move at high speeds in all directions; temperature and pressure can impact density.
melting point
the temperature at which a substance changes from a solid to a liquid
heat of fusion
the amount of energy required to change a substance from the solid phase to the liquid phase at its melting point
freezing point
The temperature at which a liquid changes into a solid
boiling point
the temperature at which a substance changes from a liquid to a gas
heat of vaporization
the amount of heat energy required to convert one kilogram of a substance from a liquid to a gas
evaporation
the escape of particles of a substance into gaseous form
condensation
the process of changing from a gaseous to a liquid.
diffusion
mixing of particles in a gas or liquid
Density
the amount of matter in a given space (volume)
formula of density
Density = Mass divided by volume
Pressure
the amount of force exerted per unit of area
pascal’s principle
When force is applied to a confined fluid, the change in pressure, is transmitted equally to all parts of the fluid
Archimedes principle
the buoyant force on an object is equal to the weight of the fluid displaced by the object
buoyancy
The ability of a fluid to exert an upward force on an object placed in it
mass
the amount of matter in an object
weight
the force of gravity on an object
force of gravity
F=mg; force of gravity on an object caused by the mass of the earth= the mass of the object (m) times the acceleration caused by gravity (g).
law of inertia
Newtons first law of motion: a body remains in the state which it is in, at rest or in motion, as long as no external force compels it to change its state
law of force versus mass
Newtons second law of motion: the rate of change of a particle is directly proportional to its mass and the force that is exerted on it. F=ma
law of action and reaction
Newtons third law of motion: For every action there is an equal and opposite reaction
work
the movement of a mass over a distance; work=Force x Distance
speed
the distance an object travels in one unit of time; s=d/t
displacement
the distance and direction of an object’s change in position from the starting point
velocity
the speed of an object and the direction of its motion; v=d/t
friction
the force that opposes the motion of one surface as it moves across another surface
acceleration
a rate of change of velocity; in can act in the direction of motion, at an angle, or opposite to the direction of motion. a=v2-v1/t2-t1
momentum
the product of an object’s mass and velocity; p=mv where p= momentum
force
A push or pull on an object; F=ma F=W/d
theory of relativity
Einstein’s theory that the speed of light is constant and that other things that seem constant, such as space and time, are not.
natural resources
materials found in nature that are used by living things
renewable resource
any natural resource (as wood or solar energy) that can be replenished naturally with the passage of time
nonrenewable resource
a resource that cannot be reused or replaced easily (ex. gems, iron, copper, fossil fuels)
cohesive behavior (surface tension), ability to moderate temperature, expansion upon freezing, versatility as a solvent (esp. salts)
special properties of water that contribute to Earth’s suitability as an environment for life
what characterizes science and its methods
empirical observations, testable questions, formation of hypothesis, and experimentation that results in stable and replicable results, logical reasoning, and coherent theoretical constructs
scientific argumentation
recognize that the strength or usefulness of a scientific claim is evaluated through ________ ________, which depends on critical and logical thinking, and the active consideration of alternative scientific explanations to explain the data presented
anomalous data
Data that do not fit with the rest of a data set
replicated
an important part of creating a scientific experiment is making sure the experiment has the ability to be _____________, or conducted elsewhere with the same outcome
inference
an explanation for an observation
qualitative observation
observations that describe what you observe
quantitative observation
observations that measure what you observe
science
the systematic and organized inquiry that is derived from observations and experimentation that can be verified or tested by further investigation to explain natural phenomena; is testable; seeks falsifications
pseudoscience
fake science; not testable; seeks confirmations (astrology and phrenology)
creative
scientists are _________ because it takes __________ity to construct scientific questions, methods, and explanations
religion
boundaries of the supernatural
arts
boundaries of personal interpretation and creative expression
science
boundaries of the natural world
technology
applied science
scientific knowledge
___________ ___________ is both durable and robust and open to change; it can change because it is often examined and reexamined by new investigations and scientific argumentation; it becomes stronger because of these frequent examinations
theories
ideas with the most durable explanatory power become established ________; culmination of many scientific investigations; well-tested hypothesis supported by empirical evidence; broad explanation of many observations; explain laws
laws
descriptions of specific relationships under given conditions in nature, but do not offer explanations for those relationships; describes how something behaves; not all _____ have accompanying explanatory theories
models
______ can be very useful tools of scientific thinking. they can take the form of a drawing, graph, three-dimensional object, computer program, or mathematical equation. Even a description in words of how a natural process works is a _____.
empirical evidence
source of knowledge acquired by means of observation or experimentation
ethics
norms for conduct that distinguish between acceptable and unacceptable behavior
kinetic energy
energy of motion dependent upon mass and speed; E(k) = 1/2mv^2
potential energy
stored energy dependent upon position and height; E(p) = mgh
Law of Conservation of Energy (LoCoE)
states that energy cannot be created or destroyed, only transformed
open system
can exchange both matter and energy with an outside system. They are portions of larger systems and in intimate contact with the larger system. Your body is an example.
closed system
exchange energy but not matter with an outside system. Though they are typically portions of larger systems, they are not in complete contact. The Earth is an example; it obtains lots of energy from the Sun but the exchange of matter with the outside is almost zero
isolated system
can exchange neither energy nor matter with an outside system. While they may be portions of larger systems, they do not communicate with the outside in any way. The physical universe is an example
work
transfer of energy received when force acts over a distance W=Fd
power
rate at which work is done P=W/t
convection
transfer of internal energy in a gas or liquid by means of currents in the heated fluid
conduction
transfer of heat between substances in direct contact
radiation
transfer of heat by means of electromagnetic waves
temperature
measure of the heat present in an object
thermal energy
total energy (kinetic + potential) in a substance
exothermic reaction
net release of energy; energy is product; feels warm; net energy negative; energy of reactants > energy of products; downhill potential energy graph
endothermic reaction
net absorption of energy; energy is reactant; feels cool; net energy positive, energy of products > energy of reactants; uphill potential energy graph
strong force, electromagnetic force, weak force, gravitational force
four fundamental forces, strongest to weakest
strong force
fundamental force that holds all nucleons together
electromagnetic force
force of electric and magnetic attraction and repulsion of charges
weak force
force of attraction between quarks, electrons, and neutrinos
gravity
mutual attraction between all objects
alpha particle
2 protons and 2 neutrons (helium nucleus); most massive; charge +2; low penetration
beta particle
1 electron; low mass; charge -1; higher penetration ability
gamma ray
high-frequency electromagnetic radiation emitted by radioactive nuclei; no mass; no charge; pure energy; highest penetration ability
half-life
time required for 1/2 the atoms in a sample of a radioactive isotope to decay; carbon-14 ~5000 years uranium-238 ~4 billion years
fission
breaking apart of nuclei; think split; atomic bombs
fusion
combining of atoms; on the Sun
nuclear
_________ reactions release much more energy than chemical reactions
chemical
in _________ reactions, matter is not created or destroyed, it simply changes form, unlike nuclear reactions
nuclear
in __________ reactions, matter can be changed into energy using E=mc^2
conductor
object that allows heat or electricity to pass through it easily (copper wire); metallic bonds –> electrons move freely
semiconductor
electrical conductivity between that of a conductor and insulator (silicon)
insulator
object that does not conduct electric current (glass); electrons do not move freely
current
rate at which electric charge flows
voltage
electrical force that drives an electric current; potential energy difference between two points in a circuit
resistance
the measure of how easily charges flow through a circuit
voltage
_______ can exist without current, but current cannot exist without _______
resistance
increasing _____________ decreases current, but not voltage
Ohm’s law
V=IR or current is equal to voltage over resistance
left
_______ of the electromagnetic spectrum (radio waves, etc) has low frequency; wavelength is long; low energy
right
______ of the electromagnetic spectrum (gamma rays) has high frequency; short wavelength; high energy
doppler effect
if the source of waves is moving toward the observer, each wave takes less time to reach the observer than the previous wave, and the frequency is increased; if the source of the waves is moving away from the observer, the frequency is reduced WHAT EFFECT IS THIS?
scalar quantities
quantities that are described by a magnitude alone (distance, speed, energy, mass, work)
vector quantities
quantities that are described by a magnitude + direction (displacement, velocity, acceleration, force, linear momentum)
speed
distance over time d=rt
velocity
speed + direction
acceleration
rate at which velocity changes change in velocity over change in time
displacement
vector difference between starting and ending position
Newton’s first law an object in motion stays in motion and an object at rest stays at rest unless acted upon by an outside force INERTIA