Physics exam2 Flashcards
simple harmonic motion
type of periodic motion
periodic motion
a motion that repeats itself over and over
period of a mass on a spring
f=-kx
type of simple harmonic motion
the force exerted by a spring is opposite in its direction to its diplacenment from equilibrium
2pi sqrt m/k
energy conservation in oscillatory motion
an ideal system has total energy conserved
there is a continual tradeoff between kinetic and potential energy
simple pendulum
consists of a mass suspended by a spring/rod of length L.
- has a stable equilibrium when mass is directly below the suspension point
- *all the mass is concnetrated at a single point
physical pendulum
the mass is NOT concentrated at a point, but instead it is distributed over a finite volume
damped oscillations
as the mechanical energy of a system decreases, its amplitude of oscillation decreases as well
Transverse waves
individual particles move at right angles (perpendicular) to the direction of wave propogation
longitudinal wave
individual particles move in the same direction (parallel) as the wave propogation
string waves
transverse waves that proppgate on a string
harmonic wave function
waves will have a shape of a sine of cosine
sound waves
a longitudinal wave of compressions and refractions that can travel through the air as well as other gases liquids and solids
sound intensity
the loudness of a sound is determined by its intensity
the doppler effect
the change in frequency due to relative motion between a source ad a receiver
supportion and interference
waves can combine to give a variety of effects
superposition
when two or more waves occupy the same location at the same time they simply add
constructive interference
waves that add to give a larger amplitude exhibit constructive interference
destructive interference
waves that add to give a smaller amplitude exhibit destructive interference
interference patterns
waves that overlap can create patterns of constructive and destructive interference
standing waves
oscillate in a fixed location
beats
occur when waves of slightly different frequencies occur
-percieved as alternating loudness and softness to the ear
ideal gases
simplified model of a rea gas in which interactions between molecules are ignored
kinetic theory of gases
a gas is imagined to be compromised of a large number of pointlike molecules bouncing off the wall of a container
origin of pressure
the pressure exerted by a gas is a result of the momentum transfers that occur every time a molecule bounces off a wall of a container
speed distribution of molecules
molecules in a gas have a range of speeds
-the maxwell distribution indicates which speeds are most likely to occur in a given gas
rms speed
speed of the molecules in a gas at kelvin T
solids and elastic deformation
when a force is applied to a solid, the size and shape may change
stress
the applied force per area
strain
the resulting deformation of stress
elastic deformation
one in which a solid returns to its original size and shape when the stress is removed
equilbrium between phases
when phases are in equilibrium, the number of molecules in each phase remains constant
evaporation
occurs when some molecules in a liquid have speeds great enough to allow them to escape into the gas phase
latent heat
the amount of heat per unit mass that must be added to or removed from a substance to convert it to one phase or anothe
latent head of fusion
the heat required for melting or freezing Lf
latent heat of vaporization
the heat required for vaporizing or condensing Lv
latent heat of subimation
the heat required to sublime a solid directly to gas, or to condense a gas to a solid Ls
electromagnetic waves
waves of oscillating electric and magnetic fields
electromagnetic spectrum
the entire range of waves with different frequencies
polarization of a beam of light
the direction along which its electric field points
polarizer
transmits light only whose electric field has a component in the direction of the polarizer’s transmission axis
polarization by scattering
light scattered by the atmosphere is polarized when viewed at right anges to the sun
polarization by reflection
when light reflects from a horizontal surface it is partially polarized in the horizontal direction
wave fronts
a surface on which the phase of a wave is constant
rays
the direction of wave propogation is indicated by rays, which are always at right angles to wave fronts
law of reflection
states that the angle of reflection theta is equal to the angle of incidence
specular/diffuse reflection
a smooth surface reflects light in a single direction. A rough surface reflects light in many directions
ray tracing
involves drawing two or three of the rays that have particularly simple behavior. These rays originate at a point on a object and intersect at the corresponding point on the image
real images
light passes through the apparant position of the image itself
virtual image
light does not pass through the image
refraction of light
the change in direction of light due to a change in its speed
index of refraction (n)
quantifies how much a medium slows the speed of light
snell’s law
relates the index of refraction and angle of incidence in one medium to the index of refraction and angle in another medium
qualitative qualities of refraction
refracted light is bent closer to the normal in a medium where its speed is reduced and away from the normal in a medium where its speed is increased
total internal refraction
when light in a medium in which its speed is relatively low encounters a medium in which its speed is greater, the light will be totally reflected back into its original medium if its angle of incidence exceeds the critical angle
total polarization
reflected light is totally polarized parallel to the surgace when the reflected and refracted rays are at right anges. Occurs at Brewster’s angle
lens
an object that uses refraction to bend light and form images
