Intro to Life and Physical Science Test 2

Wave

a distrubance that travels from one place to another transporting energy (light, gama, radio, sound, electromagnetic)

Mechanical wave

traveling through a material, requires matter to travel

example = water, sound

Electromagnetic waves

waves that can travel though a vaccum and do not require a medium

example = light waves

Peaks/troughs 

highs or lows of waves

Amplitude

how big or tall is the wave (water at rest to the top or bottom)

Wavelength

the distance (m, cm) from one peak to the next 

know as lambda

Frequency

waves there are per secound

know the nit of Hz and are measured in pitch 

Period

the time for one wave to pass

unit is T

How are period and frequency related?

If one is large the other is small

High frequency corresponds to small period 

(T = 1/v)

How are wavelength and frequency related?

High frequency then short wavelength

Vw = lambda x v

How is energy of a wave related to it’s frequency and its amplitude?

Larger amplitude than large energy

High frequency then high energy 

Transvers wave

moving up and down with vibrations at right angles

light waves

Longitudinal waves

is a type of mechanical wave where they move right to left

sound

Electromagnetic spectrum

the entire range of all types of electromagnetic radiation

What is true about speed all electromagnetic waves?

Not their speed it frequency, Gamma rays has higher frequency

Read is the lognest wave length w/ voliet being the shortest 

Violet has more energy

How is a sound wave different than a light wave?

Unlike light, sound requires a medium to travel

Vibrations are due to the wave are in the same direction as the direction of the wave travel

What makes a sound wave louder?

amplitude

What makes a higher pitch?

higher pitch = more energy and higher frequency

What does the law of refectionsay for polished objects?

the angle at which the wave is reflected = to the angle at which the wave encountered the polished barrier 

What causes light to refract?

transfers from one medium to another (waves bend and change speed)

What does a prism do?

When differnet frequencies of light are refracted by differnt amounts, the light coming in will separate into it’s colors

What does differaction have to do with shadows?

when it interacts with the edge of an object it bends into fill in the space

Waves bento the sharw region where the waves have been blocked

What does absoption have to do with the color of objects?

waves energy is taken up by an object, absorps colors that the object isn’t

What is the doppler effect?

the change in the frequency of a wave due to a relative motion b/w the source of the wave and the observer

What happens to the pitch when the source of noiseis approaching you and when it moving away from you?

High frequency means high pitch so closer means higher pitch

How do the two types of charges interact?

There are positive and negative charges and object w/ no net charge is netural

similar charges repel and opposite charges attract

What are the units for charge?

Coulombs = Q

What determines the strength and direction of the electromagnetic force? (Coulomb’s Law)

charges' magnitudes and direction

How are Colomb’s Law and Neton’s Law similar and different?

Both depend on distance, stronger when closer together

Gravity has to do w/ mass and Coulomb deals with charge

Electric potential

the amount of work required to move a unit charge

How is electric potential generated? and what are it’s units

generated by electric fields

Measured in volts

What is current? units? What engery is involed 

Converted into kinetic energy

Charged particles (usually electrons) moving through (“down”) an Electric potential

Amperes (Amps)

Conductor 

allows charged particles to move through

Salt whater and metals

Insulators

the electrons are held tightly to atoms and can NOT flow to the next atom

wood, plastic, air, glass

semi-conductors

have intermediate conductivite must add energy to flow

silicon

How does a batter work

b/w 2 termials w/ a differing electrical potential and has physically seperated charges that charges in the conductor flow from the high potential side to the lower potential side until both ends of the conductor are at the same potentialy

Magentic force

is a non contact force that results b/w a magnetic fields and electric charge

Electric force

interaction b/w 2 electrically charged particles

Similar and difference b/w magnetic and electric forces

similar = can both attract or repel

difference = you can never separate poles 

What makes a magnet different than other non-magnet metals?

Its internal atomic structure, specifically having electrons with unpaired spins that create a strong magnetic field.

Why are some metals like iron, magnetic, while other metals are not?

That does not mean every piece of iron is a magnet; it can have different “domains” of perfect magnets not aligned.

What is the relationship b/w electric fields and magnetic fields?

a changing electric field creates a magnetic field, and a changing magnetic field creates an electric field

What are electromagnetism and induction?

a current is generated when a conductor moves in a magnetic field. For example... 1) Move a magnet in or near a loop of wire 2) Spin a wire loop in a magnetic field

What are the three particles found in an atom?

protons, neutrons, and electrons

What are their charge?

protons = positive, neutrons = netural, electrons = negeative

Where in the atom are they found? and what is most of an atom made of?

protons and neutrons (mostly made of) are found in the nucleus and electrons are on the outside

What particles determine an atoms mass

protons and neutrons

What determines an atoms volume 

how many and far away the electrons are (made up mostly of empty space)

What is true of a neutral atom?

same number of protons and electrons but not always the same number of neutrons

Element

sample containing only one type of atom

What makes one element’s atoms different from any other

number of protons in an atom's nucleus

Atomic mass number

the total number of protons and neutrons in an atom's nucleus (shown top left of symbol)

Isotope

are differnt atoms of the same element with different neutrons

Ion

has a net charge 

Cation

positively charge (lost electrons)

Anion

negatively charged (gain electrons)

How is atomic mass different than the atomic mass number?

Atomic mass is the weighted average mass of an element's isotopes, while mass number is a whole number representing the total protons and neutrons in a specific atom.

The atomic mass number will be a whole number

What are columns called?

Groups (up and down) act similar

What are rows called

periods (side to side)

Who discovered the periodic table?

Mendeleev

How is the periodic table organized?

was arraged by mass

Electron shells

shells are filled starting w/ the lowest energy level

General how do electrons fill an atom’s shell

2, 8, 8  rule

Valence electrons

electrons in the outermost shell

Why are inert gases / Noble gases inert

have full number of valence electrons

What does periods and groups of the table tell you about an atom’s shells and valence eectrons?

row = total # of electron shells

columns = elements w/ same number of valence electrons and same reactivity 

What are three ways for an atom to create a full outer shell?

lose, gain, or share 

lose = cation

gain = anions

share = covalent bonds

what observation led to the discovery of electron shells

specific patterns in atomic spectra the light emitted by excited atoms

What is the difference from one shell to another in the same atom?

their distance from the nucleus and their energy level