Waves Flashcards
work
force*distance
joule
newtons * meters
power
energy/time or work done divided by given time
Kinetic energy
energy due to speed or movement
Potential energy
stored energy
Amplitude
maximum distance from equilibrium. height of wave.
frequency
how often waves are made and number of waves
wavelength
length of wave from crest to crest or trough to trough
transverse wave
wave on a string
longitudal wave
sound wave or push wave
wave speed
frequency*wavelength
Like a transverse wave, a longitudinal wave has
amplitude, frequency, wavelength, and speed.
The vibrations of a transverse wave move in a direction
at right angles to the direction of wave travel.
The vibrations of a longitudinal wave move in a direction
along the direction of wave travel.
An object that completes 10 vibrations in 20 seconds has a frequency of
0.5 hertz
If the frequency of a certain wave is 10 hertz, its period is
0.1 seconds
A floating leaf oscillates up and down two complete cycles each second as a water wave passes by. What is the wave’s frequency?
2 hertz
The amplitude of a particular wave is 1 meter. The top-to-bottom distance of the disturbance is
2 m.
On some days, air nearest the ground is colder than air that is higher up. On one of these days, sound waves
tend to be refracted downward.
True or false: Sound waves can interfere with one another so that no sound results.
True
The object with the highest natural frequency is a
small bell.
Sound will be louder if a struck tuning fork is held
with its base against a tabletop.
A base fiddle is louder than a harp because of its
sounding board
Sound waves cannot travel in
a vacuum.
Compressions and rarefactions are characteristic of
longitudinal waves.
Most of the waves in the electromagnetic spectrum are
invisible
Radio waves travel
always much faster than sound waves.
Which electromagnetic waves have the longest wavelength?
radio waves
Sunburns are produced by
ultraviolet light
Which color of light gets through red glass?
red
The fact that you can see stars in the nighttime sky is evidence that
light can travel in a vacuum and our atmosphere is transparent to visible light.
Compared to its average speed in air, the average speed of a beam of light in glass is
less.
Compared to the photon that enters a pane of window glass, the photon that emerges is
an identical but different photon.
Glass is transparent to
visible light.
Materials generally become warmer when light is
absorbed by them
The sensation of color is seen when light falls on the eye’s
cones
The physics underlying the redness of sunsets and the color of blue jays involves
scattered sunlight.
Light is reflected when
incident light is returned into the medium from which it came.
The type of lens that spreads parallel light is a
diverging lens
Refraction occurs when light passing from one medium to another
changes speed
The type of lens that brings parallel light rays together is a
converging lens
What types of light have sufficient energy to break bonds?
gamma rays, x-rays, UV
UV
ultraviolet, breaks bonds
IR
infrared, makes molecules vibrate
microwaves
make molecules spin
The fundamental force underlying all chemical reactions is
electrical
The fundamental force underlying all chemical reactions is
electrical
A fundamental rule of electricity is that
like kinds of charges repel and unlike kinds of charges attract
An electron and a proton
attract each other
The vast numbers of electrons in a coin don’t fly off the surface because
they are attracted by an equal number of protons
The pair of protons in the nucleus of a helium atom
attract a pair of orbiting electrons.
neutrons
do not have an electrical charge
To say that electric charge is conserved means that no case has ever been found where
net charge has been created or destroyed
To become a negative ion, an atom must
gain an electron
To become a positive ion, an atom must
lose an electron
Two protons attract each other gravitationally and repel each other electrically. The stronger of these two forces is
electrical
Conducting materials are composed of atoms with
loose outer electrons
Insulating materials are composed of atoms with
tightly bound outer electrons
Rub electrons from your hair with a comb and the comb becomes
negatively charged
A negatively-charged rod is held near an aluminum can that rests on a dry wood table. If you momentarily touch the opposite side of the can with your finger, the can becomes
positively charged
A balloon will stick to a wooden wall if the balloon is charged
positively or negatively.
Just as a sustained flow of water in a hydraulic circuit needs a pump, in electric circuits the flow of charge needs
voltage
Current in a conductor can be increased by
reducing its resistance or increasing the voltage across it.
In units of measurement, power in watts is equal to
amperes*volts
In a circuit powered by a battery, charge
is energized by and flows through the battery
Conductors
carries electricity (metals, salt water)
insulators
stops electricity (most nonmetals, most plastics)
medium
what waves use to travel through, sound uses air. light doesn’t need a medium
primary colors in light
red, blue, green
electricity
charge that’s moving
Which of the following are true for most conductors?
Electrons are shared in a “sea” of electrons and are free to move.
ion
charged particle
a charge on an insulator
stays where its put
US voltage
110-120 voltage
batteries
make potential energy
watts
power in a system
volts
pressure against electrons in a systems
ohm
resistance
current
how many electrons move through a system in a time period.
ohm’s law
current=voltage/resistance
equation for watts
volts*amps
