Chart Navigation & Plotting · Tidal Currents
In the Tidal Current Tables, 'slack water' is the moment when:
- AThe current speed is at its maximum
- BThe current reverses and its speed is momentarily zero✓ Correct
- CThe tide is highest
- DThe tide is lowest
Explanation
Slack water is the instant of zero current velocity between flood and ebb. Maximum flood and maximum ebb (the strongest currents) occur roughly midway between slacks — note that slack water does not necessarily coincide with high or low tide.
Authority: NOAA Tidal Current Tables
Practice the full Chart Navigation & Plotting bank
Free spaced-repetition quizzing across 2190 USCG exam questions — it schedules your reviews so the ones you miss come back until they stick.
Related Chart Navigation & Plotting questions
- Tidal Currents
A 'flood' current is one that:
- Chart Basics
On a Mercator chart, one nautical mile is measured using the:
- Chart Basics
The principal advantage of the Mercator projection for navigation is that:
- Chart Basics
Charted depths (soundings) on a U.S. chart are referenced to which tidal datum?
- Chart Basics
Vertical clearances of bridges and overhead cables on a U.S. chart are normally referenced to:
- Distance, Speed & Time
A vessel makes good 12 knots. How far does it travel in 20 minutes?