Question

exam lesson name: light and sound
exam number: 700699rr
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question 2 of 20 :
select the best answer for the question.

1. sound waves cannot travel through a/an

○ a. liquid.
○ b. vacuum.
○ c. elastic material.
○ d. solid.

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Explanation:

Sound waves are mechanical waves that require a medium (matter) to travel, as they propagate by vibrating particles. A vacuum is a space with no matter (no particles), so sound waves can't travel through it. Liquids, elastic materials, and solids all have particles that can vibrate to transmit sound.

Answer:

B. vacuum.