When a book is dropped onto a wooden desk, the molecules in the wood begin to vibrate from the force of the book. Which of these is produced by the vibrations?
A B C D
friction interference sound waves ultrasonic waves
Question: When a book is dropped onto a wooden desk, the molecules in the wood begin to vibrate from the force of the book. Which of these is produced by the vibrations?
(A) friction
(B) interference
(C) sound waves
(D) ultrasonic waves

Answer: (C) sound waves
Answer: (B) interference
Question: When a book is dropped onto a wooden desk, the molecules in the wood begin to vibrate from the force of the book. Which of these is produced by the vibrations?
(A) friction
(B) interference
(C) sound waves
(D) ultrasonic waves
Answer: (C) sound waves