A swimming duck paddles the water with its feet once every

PHYSICS · Multi-part · AP · Physics 2: Algebra-based · Waves Sound and Physical Optics · Waves Sound and Physical Optics

Problem

1.6\,\text{s}

, producing surface waves with this period. The duck moves at constant speed in a pond where the speed of surface waves is

0.32\,\text{m s}^{-1}

, and the crests of the waves ahead of the duck are

0.12\,\text{m}

apart. (a) What is the duck's speed? (b) How far apart are the crests behind the duck?