Phys Flashcards
Voltage of a circuit equation is
V = IR
Index of refraction equation
n = c/v c is the speed of light in a vacuum, 3.0x10^8 m/s
The intensity of the radiation emitted is directly proportional to
The energy of electromagnetic radiation is directly proportional to the number of photons (emitted)
How is wavelength related to energy of the light?
wavelength is inversely related to energy of the light. Shorter wavelengths are higher energy and longer wavelengths are lower energy.
How is the energy of a photon related to the frequency of the light?
E = hf h is planck’s constant.
Pressure differentials equation
ΔP = CO x TPR CO is cardiac output TPR is total peripheral resistance.
Work equation
W=P/T (W/s = kJ)
W=ΔKE = ½mv2 or ½kx2 (elastic)
W= mgh
Standard state conditions
298K, 1 atm, 1M conc
gamma decay
the emission of photons by the nucleus, atomic mass and number do not change.
beta decay
emission of an electron, atomic mass does not change, atomic number increases
beta plus decay
emission of a positron, atomic mass does not change, atomic number decreases
alpha decay
occurs in large nucleus atoms, atomic mass decreases by 4, atomic number decreases by two
The change in entropy is positive or negative when solids change to gas?
positive entropy
negative gibbs free energy change means the reaction is
spontaneous
A stationary receiver detects a change in frequency of the signal from a jet flying directly away from it at 300 m/s. Which of the following receivers will detect the same change in frequency from a jet moving away at 600 m/s? -A receiver moving at 900 m/s in the opposite direction as the jet -A receiver moving at 300 m/s in the opposite direction as the jet -A stationary receiver -A receiver moving at 300 m/s in the same direction as the jet
A receiver moving at 300 m/s in the same direction as the jet
How does voltage difference relate to energy of an electric field?
Ed = ΔV ΔV= W/q = kQ/r
Period equation
T = 1/f
How are wavelength and frequency related?
λ=c/f
An astronomer observes a hydrogen line in the spectrum of a star. The wavelength of hydrogen in the laboratory is 6.563 x 10-7m, but the wavelength in the star’s light is measured at 6.56186 x 10-7m. Which of the following explains this discrepancy? -The star is moving away from Earth. -The star is approaching Earth.
The star is approaching Earth.
Photoelectric effect equation relating kinetic energy, energy and work
K= hf-W E=hf=hc/λ
Half life equation
n=n0e^ -λt
velocity of a wave equation
v=f λ
In standing waves: the end of strings is always _______
nodes
In standing waves: strings equations are
λ= 2L/n (n is relates to the number of humps) f=nv/2L
In standing waves: open pipes equations are
λ=2L/n (n is the number of nodes) f=nv/2L
In standing waves: open pipes always end in
Antinodes (open ended)
In standing waves: closed pipes equations are
λ=4L/n (n is the number of halves of humps 1,3,5….. always odd) f=nv/4L
In standing waves: closed pipes always start with ______ and end with _______
A node, an antinode
Electrical Potential Energy equation
V = U/q = E*d
U=q*ΔV = q*Ed = k*Q*q/r
Coulomb’s Law equation
F (kq1q2)/r^2
Electric Field energy equation
E=F/q=Q/r^2 Units N/C or V/M
What is Wout/Win represent?
Efficiency of a machine. Wout/Win = (load)(load distance)/(effort)(effort distance)
Describe mechanial advantage
Mechanical advantage is the ratio of magnitudes of the force exerted on an object by a simple machine (Fout) to the force of actually applied on the simple machine (Fin).
How does work relate to force?
W = F*d*cos(Ø)
Elastic Potential energy
U = ½kx2
What are the two components of force on inclinded planes?
Fg(parallel) = mg sinø
Fg(perpendicular) = mgcosø
What is the equation for torque (rotational equalitibrium)
T = rF sinø
In sound or pain what is the lowest point of the threshold
sensitivity
How is Standard Gibbs Free Energy related to Keq
ΔG˚ = -RTlnKeq
How is power related to voltage?
P = V2/R = I2R = IV
Pressure guage equation
P=pgz
Pressure difference in guage is Pg=P-Patm
Buoyant force equation
FB=pliquidgvsubmerged
What is absolute pressure?
Absolute pressure in a fluid due to gravity somewhere below the surface is given by the equation P=P0+pgz
Describe Pascal’s Principle
P= F1/A1 = F2/A2 so A1d1=A2d2
W=F1d1=F2d2
A change in the pressure applied to an enclosed fluid is transmitted undiminished to every portion of the fulid and to the walls of the containing vessel.
What is capacitance?
Capacitance is the ability to store charge per unit voltage.
C = Q/V
Rate the speed at which sound travels through from fastest to slowest
air, liquid, solid, vaccum
- solid
- liquid
- air
doesn’t travel in a vaccum
Rate the speed at which light travels through these mediums (fastest to slowest)
air
vaccum
water
glass
- vaccum
- air
- water
- glass
decreasing speed, increasing index of refraction
What is a galvanic cell?
redox reaction has a negative ΔG (spontaneous)
there’s a salt bridge
oxidation occurs at the anode (negative), electrons travel from the anonde to the cathode (positive), where reduction occurs
What is an electrolytic cell?
The cell has a positive ΔG, nonspontaneous. Therefore electrial energy is required to start a reaction.
electrons travel from the cathode (is negative) to the anode (is positive)
emf is negative
