# Airy wave theory: Quiz

Question 1: In case of deep water — by which is meant ________ water depth, from a mathematical point of view — the flow velocities have to go to zero in the limit as the vertical coordinate goes to minus infinity: z → -∞.
NumberTransfinite numberLarge numbersInfinity

Question 2: Further, by using the ________, wave shoaling and refraction can be predicted..
WKB approximationQuantum mechanicsSchrödinger equationQuantum tunnelling

Question 3: [1] Soon after, in 1847, the linear theory of Airy was extended by Stokes for ________ wave motion, correct up to third order in the wave steepness.
Control theoryNonlinear systemDynamical systemChaos theory

Question 4: The wave number k (and wave length λ) are independent of the ________, and have no Doppler shift (for monochromatic waves).
Centrifugal force (rotating reference frame)Inertial frame of referenceFrame of referenceFictitious force

Question 5: which is an exact result for periodic progressive water waves, also valid for ________ waves.
Dynamical systemChaos theoryControl theoryNonlinear system

Question 6: The theory assumes that the fluid layer has a uniform mean depth, and that the ________ is inviscid, incompressible and irrotational.
Surface tensionFluid mechanicsViscosityFluid dynamics

Question 7: On the other hand, in a ________ moving with the mean velocity U (so the mean velocity as observed from this reference frame is zero), the angular frequency is different.
Inertial frame of referenceCentrifugal force (rotating reference frame)Frame of referenceFictitious force

Question 8: ________ — real water waves as seen in the ocean and sea
Wave shoalingRip currentWind waveBreaking wave

Question 9: However, in nonlinear waves this is no longer the case and the particles exhibit a ________.
Airy wave theoryStokes driftDispersion (water waves)Boussinesq approximation (water waves)

Question 10: The bed being impermeable, leads to the ________ bed boundary-condition:
Rigid bodyClassical mechanicsKinematicsForce