PADI Divemaster Certification Practice Exam

What type of wave occurs on moderately steep beaches and has a distinct forward curl?

1. Spilling breaker

2. Surging breaker

3. Plunging breaker

4. Shallow breaker

The correct answer is: Plunging breaker

A plunging breaker is characterized by its distinct forward curl and occurs on moderately steep beaches. This type of wave develops when the crest moves faster than the base due to the underwater topography. As the wave approaches the shore, it becomes steep, and when it collapses, the crest curls over, creating a dramatic and powerful breaking effect. This dynamic is typically seen on beaches with sufficient incline where the wave has enough energy to create a steep wave face before it breaks. In contrast, spilling breakers, which occur on gently sloping beaches, display a gradual spilling motion instead of a distinct curl. Surging breakers tend to form on steep beaches but do not curl in the same way as plunging breakers; their energy causes them to surge up the beach without a significant break. Shallow breakers is not a recognized term in ocean wave dynamics, making it less applicable to this context. Thus, the nature and formation of a plunging breaker align perfectly with the described wave characteristics.