definitions Flashcards
simple harmonic motion
special type of periodic motion where the restoring force is proportional to the object’s displacement and acts towards the object’s equilibrium position
oscillation
repetitive variation of some measure about a point of equilibrium or between two or more different states.
transverse wave
wave that vibrates perpendicular to the direction of propagation of the wave
longitudinal wave
wave that vibrates parallel to the direction of the propagation of the wave
parts of transverse waves
crests, troughs
parts of longitudinal waves
compressions, rarefactions
ray
idealized model of light, obtained by choosing a line that is perpendicular to the wavefronts of the actual light
wavefront
is the set of all points where the wave has the same phase
frequency of the visible light
4 × 10^14 - 8 × 10^14 Hz
wavelength of visible light
380 - 750 nm
light spectrum
gamma rays, x-rays, ultraviolet rays, visible light, infrared rays, microwaves, radio waves
light
electromagentic wave
polarized light
light that oscillates in one particular plane perpendicular to the direction of propagation
internal energy
sum of kinetic and potential energy of a substance
heat
energy which is transferred from one thermodynamic system to another
ideal gas
a theoretical model of gas with no intermolecular forces and constant internal energy of particles and where volume of each molecule is negligible to the volume of whole gas
types of error
systematic error, random error
optically active substance
substance that rotates the plane of polarization of light that passes through it
electric potential
work done per unit charge moving a small positive test charge from infinity to that point
conventional current
electric current opposite to the direction of electron flow
drift velocity
speed of electrons due to current
potential difference
work done by moving a positive test charge/mass point from one point to another in an electric/gravitational field
gravitational field
region of space where a mass experiences force due to another mass
gravitational field strength
force per unit mass experienced by a small test mass placed in a field (unit: N/kg)
gravitational potential
work done per unit mass moving a small test mass from infinity to that point (unit: Nm/kg)
electric field
region of space where a charged object experiences force due to another charged object
electric field strength
force per unit charge experienced by a small positive test charge placed in a field (unit: N/C)
magnetic field
region of space where a test magnet experiences a turning force
magnetic flux density
quantity used to measure the strength of a magnetic field (unit T)
magnetic flux
magnetic field strength times the area swept out conductor (unit: Wb)
electric potential
work done per unit charge by moving a small positive test charge from infinity to that point (unit: Nm/C)
emission spectrum
frequencies of electromagnetic radiation emitted due to an electron making a transition from a high energy state to a lower energy state
absorption spectrum
specific light frequencies absorbed by cool gases between the source of light and the scope raising atom to an excited state
continuous spectrum
spectrum with all light frequencies
work function
minimum energy required to eject an electron from a metal surface as a result (this energy is larger for electrons at lower energy levels)
photoelectric effect
emission of electrons from a metal surface as a result of the absorption of electromagnetic wave energy
De Broglie hypothesis
all moving particles have a matter-wave associated with them (they have wave-like properties)
Heisenberg uncertainty principle
fundamental limit to the possible accuracy of any physical measurement
threshold frequency
minimum frequency of light needed to allow photoelectrons to be emitted from an atom
nuclide
particular species of an atom with contains specific number of protons and neutrons
isotopes
nuclei with the same number of protons but different number of neutrons
ionisation
occurs when electrons are removed from an atom
mass defect
difference between mass of the nucleus and masses of its component nucleons
binding energy
energy required to break the nucleus into its constituent nucleons
critical mass
the smallest amount of fissile material needed for a sustained nuclear reaction
coherent light
oscillations with the same frequencies and constant phase difference
escape speed
speed of a rocket needed to escape the gravitational attraction of the planet, which means getting to infinite distance away
isochronous pendulum
pendulum with period not dependent on amplitude of the oscillations
decay constant
probability of decay of nucleus in one second
RC circuit time constant
time required to charge the capacitor to 63.2% of the applied voltage
