Correct Detailed Answers (Verified Answers)
Graded A+
When is strangeness conserved? - Correct Answer - Strong interactions
principle of moments - Correct Answer - object in equilibrium:
sum of clockwise moments = sum of anticlockwise moments about a point
progressive waves - Correct Answer - waves which travel through a substance or space
if electromagnetic
projectile - Correct Answer - projected object in motion acted on only by the force of
gravity
random error - Correct Answer - error of measurement due to readings that vary
randomly with no recognisable pattern, trend or bias
range of readings - Correct Answer - difference of minimum and maximum reading
range of instrument - Correct Answer - minimum and maximum reading that can be
obtained using the instrument
energy - Correct Answer - capacity to do work
energy levels - Correct Answer - discrete energy levels that electrons take in shells of
atom
pg. 1
,equilibrium - Correct Answer - object in rest or constant motion
error bar - Correct Answer - uncertainty representation on a graph
error of measurement - Correct Answer - uncertainty of a measurement
excitation - Correct Answer - process in which atom absorbs energy without becoming
ionised when electron moves from inner shell to higher energy level in outer shell
first harmonic - Correct Answer - pattern of stationary waves on a string when it
oscillates at lowest possible frequency
fluroescence - Correct Answer - emission of visible photons after atoms deexcite
frequency - Correct Answer - number of cycles of a wave that pass a point per second
friction - Correct Answer - force opposing the motion of a surface that moves or tries to
move across another surface
gamma radiation - Correct Answer - high energy photons emitted by unstable nuclei or
produced in particle annihilations
gravitational field strength - Correct Answer - force per unit mass on small object in
gravitational field
ground state - Correct Answer - lowest energy state of an atom
hadron - Correct Answer - particles and anti that can interact through the strong
interaction
pg. 2
,Hooke's Law - Correct Answer - the extension of a spring is proportional to the force
applied to it
inertia - Correct Answer - resistance of an object to a change of its motion
interference - Correct Answer - formation of points of cancellation and reinforcement
where two coherent waves pass through each other
internal resistance - Correct Answer - resistance inside the source of electrical energy -
loss of PD per unit current in the source when current passes through it
ion - Correct Answer - charged atom
ionisation - Correct Answer - process of creating ions
How are strange particles created? - Correct Answer - Strong interactions
How to strange particles decay? - Correct Answer - Weak interactions
Couple - Correct Answer - Pair of equal and opposite forces acting upon the same body
but not along the same line
Critical angle - Correct Answer - The angle of incidence of a light ray must exceed this
angle for total internal reflection to occur
Critical temperature - Correct Answer - Temperature at or below which a
superconducting material has zero resistivity
Cycle - Correct Answer - Interval for an oscillating particle from a certain displacement
and velocity to the next time the particle has identical displacement and velocity
pg. 3
, de Broglie hypothesis - Correct Answer - Matter particles have a wave-like nature
de Broglie wavelength - Correct Answer - Wavelength of a matter particle
deexcitation - Correct Answer - process by which atom loses energy by photon emission
as electron moves to lower energy level - inner shell
denisty - Correct Answer - mass per unit volume for substance
diffraction - Correct Answer - spreading out of waves that pass through gap or near
edge
diffraction grating - Correct Answer - plate with close parallel slits on it
dispersion - Correct Answer - splitting of beam of white light into colours by prism
displacement - Correct Answer - distance in a given direction from equilibrium position
drag force - Correct Answer - force of fluid resistance on an object moving through fluid
ductile - Correct Answer - stretches easily without breaking
efficiency - Correct Answer - ratio of useful energy transferred to energy supplied to it
output power/input power
elastic limit - Correct Answer - point beyond which wire is permanently stretched
pg. 4