A submarine sends out high-frequency sound waves (sonar) to detect obstacles under the water. The sound waves travel through the water, strike a nearby reef, and return to the submarine's detector.
Why do the sound waves return to the submarine?
The sound waves are diffracted.
The sound waves are reflected.
The sound waves are refracted.
The sound waves are absorbed.
295 exam-style questions on CIE IGCSE Physics Sound, covering Sound. Each one has a worked solution and a mark scheme showing where the marks go.