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Demo workspace Tidewatch is a made-up tide API. The lessons are real laluka lessons about it. Your own repos arrive with sign-in.

A tide is a sum of cosine waves called constituents

Origin: baselineStatus: confirmedRepo: tidewatch-apiWritten: 19 Sept 2026
Level
juniormidsenior

What

A prediction is the sum of constituents, each a cosine with an amplitude, a speed in degrees per hour and a phase. M2 is the main lunar constituent and S2 the main solar one.
Cites
[1]

Cites

  1. [1]src/predict.ts:3-4matchSupports: what
    [lines 3-4 of a 15-line file]
    // A constituent is one cosine wave of the tide: M2 is the main lunar one, S2 the main solar one.
    export interface Constituent { name: string; amplitudeM: number; speedDegPerHour: number; phaseDeg: number; }

Card

What are the three numbers that define a tidal constituent?
junior
Show the answer
Amplitude in metres, speed in degrees per hour, and phase in degrees.
Cites[1]