Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
98 Cards in this Set
- Front
- Back
|
Photoelectric effect |
If light of high frequency (UV or blue typically) hits metal in a vacuum, the metal atoms emit electrons emitting electrons create a current |
|
|
Threshold Frequency (Ft) |
minimum frequency of light that causes ejection of electron(s) value is material dependent all-or-nothing |
|
|
Photon |
E = h*f h is planck's constant 6.626 X 10^-34 J*s Kmax = h*f - h*ft where ft is the threshold frequency and Kmax is maximum potential KE of the ejected electron |
|
|
Fluorescence |
stepwise photon emission return to ground state results in one or more intermediate excited states given energy transition << initial energy absorbed, photons released are in visible range |
|
|
Mass defect |
E = mc2 apparent loss in mass when nucleons come together |
|
|
binding energy |
allows nucleons to bind together in the nucleus |
|
|
strong nuclear force |
overcomes the repulsive electromagnetic force between protons and hold nucleons together strongest of the four fundamental forces |
|
|
Four fundamental forces |
1. Gravitational 2. Electrostatic 3. Strong nuclear force 4. Weak nuclear force |
|
|
Fusion vs Fission |
Fusion = small nuclei combine to form larger nucleus
Fission = large nucleus splits into smaller nuclei |
|
|
Alpha Decay |
emission of an alpha-particle (He 4,2) nucleus |
|
|
Beta Decay |
emission of a beta-particle (e- or beta-, beta+) in beta-, a neutron is converted to a proton in beta+, a proton is converted to a neutron no change in mass number |
|
|
Gamma Decay |
emission of gamma rays (high frequency photons) no change in mass or atomic number |
|
|
Electron Capture |
inner electron combines with proton to form a neutron and releasing a neutrino reverse of negative beta decay |
|
|
Exponential Decay |
n = n0*e^(lamda*t) where lamda is the decay constant and equal to ln2/half-life |
|
|
Accuracy vs. Precision |
accurate is ability to measure a true value whereas precision is ability to obtain a narrow range consistently |
|
|
density of water |
1 g/cm^3 or 1000 kg/m^3 |
|
|
Atmospheric Pressure |
changes with altititude |
|
|
Aboslute (hydrostatic) pressure |
total pressure that is exerted on an object that is submerged in a fluid P = Po + rho*g*z rho = density, Po is incident or ambient pressure, z is depth, g is gravity |
|
|
Gauge Pressure |
amount of pressure in a closed space above and beyond atmospheric pressure Pgauge = P - Patm = (Po + rho*g*z) - Patm |
|
|
Pascal's principle |
for an incompressible fluid a change in pressure will be transmitted undiminished to every portion of the fluid and to the walls of the containing vessel P = (F1/A1) = (F2/A2) |
|
|
Archimedes' principle |
body wholly or partially immersed in a fluid will be buoyed upwards by a force equal to the weight of the fluid that it displaces |
|
|
Surface tension |
results from cohesion, which is an attractive force that a mlc of liquid feels towards another mlc with the same property |
|
|
Adhesion |
attractive force that a mlc of lquid feels toward mlcs of some other substance |
|
|
Describe the relationship between cohesive and adhesive forces with the formation of a concave menicus versus a convex meniscus |
concave = adhesive > cohesive convex = cohesive > adhesive |
|
|
inviscid |
fluids with no (aka minimal) viscosity |
|
|
visocity |
measure of a fluid's internal reistance to flow therefore more viscous fluids will "lose" more energy while flowing |
|
|
Poiseuille's Law |
applies to laminar flow through a pipe or confined space rarely tested equation but note that assuming constant flow rate a slight change in radius results in large change in pressure |
|
|
Critical speed |
speed of which if a fluid exceeds, the fluid will start to exhibit turbulence |
|
|
Continuity Equation |
fluids willl flow more quickly through narrow passages and more slowly through wide passages Q = V1*A1 = V2*A2 where V is linear speed and A is CX area |
|
|
Bernoulli's equation |
sum of static pressure and dynamic pressure will be constant within a closed container for an incompressible fluid not experiencing viscous drag |
|
|
Transverse versus Longitudinal Waves |
Transverse = direction of the particle oscillation is prependicular to the propagation of the wave (e.g. visible light, microwaves, and X-rays) Longitudinal = particles of the wave oscillate parallel to to the direction of propagation (e.g. sound waves) |
|
|
wavelength |
distance betwen one maximum of the wave to the next maximum of wave is also known as crest |
|
|
Frequency |
# of wavelengths passing a fixed point per second units are Hertz (Hz) |
|
|
Speed of a wave (v) |
|
|
|
Period (T) |
T = 1/f where f is frequency seconds per cycle |
|
|
angular frequency |
|
|
|
Phase difference |
measure of how "in step" or "out of step" waves are from each other 0 if crests and troughs line up |
|
|
Traveling wave |
a crest is observed to be moving or progressing through a medium
|
|
|
Principle of Superposition |
when waves interact with each other, the displacement of the resultant wave at any point is the sum of the displacements of the two interacting waves constructive -> two waves perfectly in phase destructive -> resultant wave is difference |
|
|
Standing waves |
wave forms in which points in the wave are observed to be at rest resting points = nodes antinodes = points midway between nodes that fluctuate with maximum amplitude |
|
|
Forced oscillation |
if a periodically varying force is applied to a system, the system will be driven at a frequency equal to the frequency of the force |
|
|
Resonance/resonating |
frequency of periodic force equals natural resonant frequency and the amplitdue of the oscillation is at a max |
|
|
What is one situation that will always form a standing wave? |
two waves of the same frequency traveling in oposite direction interfere with one another as they travel through the same medium |
|
|
Describe the difference between closed and open boundaries with respect to oscillation and nodes/antinodes. |
closed = no oscillation and correspond to nodes open = allow maximal oscillation and correspond to antinodes |
|
|
Harmonic for strings and open pipes versus for closed pipe |
for strings and open pipe - number of half-wavelengths supported by the string for closed pipes - number of 1/4 wavelength supported by the pipe |
|
|
Fundamental frequency (first harmonic) |
lower frequency (longest wavelength) of a standing wave that can be supported in a given legnth of string |
|
|
What is the relationship between wavelength of a standing wave and the length of a string that supports it? (open pipe and strings) |
where L is length, n is harmonic, and lamda is wavelength |
|
|
What is the difference between strings attached at both ends and open pipes? |
For strings - the # of antinodes will tell you the harmonic For pipes - the # of nodes will tell you the harmonic |
|
|
Closed pipes |
closed at one end and open at the other |
|
|
What is the equation that relates the wavelength of standing wave and the length of a closed pipe? |
where n can only be odd integers |
|
|
Sound |
longitduinal wave transmitted by oscillation of particles in a deformable medium cannot travel through a vacuum |
|
|
Speed of Sound |
where B is the bulk modulus, measure of medium's resistance to compression Bgas < Bliquid < Bsolid rho is density of the medium |
|
|
Doppler Effect |
where top sign is towards and bottom sign is away f' > f is toward f' < f if away f' is perceived where f is the actual frequency |
|
|
Describe Doppler Effect as it pertains to light. |
If the source of light is moving toward the detector, the observed frequency will increase , which is known as blue shift since blue is at the high-frequency end of the visible spectrum Moving away is called red shift |
|
|
Intensity of Sound |
I = P/A where P is Power in watts and A is area in meters squared |
|
|
Sound Level - decibels (dB) |
|
|
|
How do mirrors produce images compared to lenses? |
Concave and convex mirrors produce images by reflection concave and convex lenses produce images by refraction |
|
|
Rank the waves of the electromagnetic specturm in order of greatest frequency/energy to lowest. How would ranking by wavelength change the ranking order? |
gamma rays > x-rays > UV > visible light > infrared > microwaves > radio waves by wavelength list will be reversed |
|
|
Electromagnetic waves |
transverse waves with oscillating electric and magnetic field vectors perpendicular to the direction of propagation the magnetic and electric field vectors are also perpendicular to each other |
|
|
Speed of light |
All electromagentic waves in a vacuum travel at the speed of light c = 3 X 10^8 m/s |
|
|
Visible region |
400 nm (violet) to 700 nm (red) ROY G. BIV |
|
|
White light versus blackbody |
white light contains all colors in equal intensity blackbody is an ideal absorber of all wavelengths of light |
|
|
What is the color an object dependent on? |
light that it reflects and does not absorb |
|
|
Reflection and the Law of Reflection |
rebounding of incident light waves at the boundary of a medium Law of Reflection - incident angle = reflected angle relative to the normal |
|
|
Plane Mirrors |
flat reflective surfaces that cause neigth convergence or divergence of the reflected light rays create virtual images at the same distance behind the mirror as the object is in front |
|
|
Concave mirrors and Convex lenses are converging systems. |
Convex mirrors and Concave lenses are diverging systems that only produce virtual and upright images. |
|
|
Center of curvature & radius of curvature |
Center of curvature (C) is point on the optical axis located at a distance equal to the radius of curvature (r) from the vertex of the mirror |
|
|
Focal length |
distance between focal point and the mirror for spherical mirrors, f = r/2 |
|
|
Optics Equation |
|
|
|
magnification |
m = - i /o negative m indicates inverted positive m indicates upright |
|
|
General rules for ray diagram for a mirror. |
1. Ray parallel to axis reflects back through focal point 2. ray through focal point reflects back parallel to the axis 3. ray to center of mirror reflects back at same angle relative to normal |
|
|
Sign Conventions for Mirrors |
|
|
|
Refraction |
bending of light as it passes from one medium to another and changes speed speed through any medium always less than speed through a vacuum |
|
|
Index of refraction |
n = c / v n = 1 for a vacuum |
|
|
Snell's Law |
pertains to refracted rays if light travels into a medium where n is smaller the light will bend away from the normal |
|
|
Total Internal Reflection = light incident on a boundary is reflected back into the original material, when angle of incidence is greater than the critical angle |
|
|
|
Thin Spherical Lenses |
focal lengths are equal so speak of one focal length for the system optic equation applies |
|
|
Converging versus Diverging Lenses |
Converging is always thicker in the middle |
|
|
Real lenses |
thickness cannot be neglected and focal length is related to the curvature of the lens surfaces adn the index of refraction of the lens |
|
|
Lensmaker Equation |
applies to real lenses |
|
|
General rules for ray diagram for a lens. |
1. ray parallel to axis refracts through focal point of front face of the lens 2. ray through or toward focal point before reaching lens refracts parallel to axis 3. ray to center of the lens continues straight through without refraction |
|
|
Sign Convention for Lenses |
|
|
|
Power of a lens |
P = 1/ f where f is focal length and Power is measured in Diopters |
|
|
Hyperopia versus myopia How are they corrected for? |
hyperopia = farsightedness requires convergence of light
moypia = nearsightedness requires divergence of light |
|
|
Dispersion Explain chromatic dispersion. |
separating of various wavelengths of light index of refraction for shorter wavelengths is greater than index of refraction for that of longer wavelengths --> longer wavelengths will have a greater angle of refraction if n1 < n2 |
|
|
Diffraction |
spreading out of light as it passes through a narrow opening (smaller than the wavelength) around an obstacle opening approaches size on the order of the wavelengths |
|
|
Slit-lens system |
if lens placed between a narrow slit and a screen, pattern is observed bright central fringe with alternating dark and bright fringes on each side central fringe is 2 times as wide as fringes on the sides and gets wider as the slit becomes narrower |
|
|
Location of Dark Fringes (minima) for single split system |
|
|
|
Location of Minima for multiple slit systems |
|
|
|
Plane-polarized light |
electric fields of all waves are oriented in the same direction |
|
|
Hill's criteria |
components of an observed relationship that increase the likelihood of causality in the relationship 1. temporality 2. strength 3. dose-response relationship 4. consistency 5. plausibility 6. consideration of alternative explanations 7. experiment 8. specificity 9. coherence |
|
|
Observation bias aka Hawthorne effect |
behavior of study participants is altered simply because they recognize that they are being studied |
|
|
What are the four principles of medical ethics? |
1. beneficence 2. nonmaleficence 3. autonomy 4. justice |
|
|
equipose |
lack of knowledge about which arm of research study is better for the subject |
|
|
What are the three types of systems? Do they exchange energy or matter with their surroundings? |
Isolated = no exchange of either Closed = exchange energy but not matter open = both energy and mass exchange |
|
|
What is the first law of thermodynamics? And how are signs assigned? |
Internal Energy = Q - W Internal Energy is positive if temperature is increasing Q is positive is heat flows into the system W is positive under expansion if work is done by the system |
|
|
What are three types of heat transfer? |
1. Conduction = direct transfer of energy from mlc to mlc via molecular collisions 2. Convection = transfer of heat by the physical motion of a fluid over a material; confined to gas and liquids only 3. Radiation = transfer of energy by electromagnetic waves |
|
|
Rules for determining signs for images and mirrors. |
I (eye) am positive that real is inverted. 1) eye is located behind a lens (think camera) 2) f is negative for diverging system and f is positive for converging system 3) object distance is almost always positive 4) if image is on the same side as the eye then it is positive |
