Question

sound is made up of vibrations, or sound waves. when something vibrates, like a plucked guitar string, it sets off a chain reaction in the particles around it which creates the waves that our ears hear as sound. how fast or slow sound waves travel is determined by the material they pass through. for example, waves travel slowest through gases, like the air around us, because the particles in gases are spaced farther apart. the more dense a material is, the closer together its particles are packed, causing the particles to collide more frequently and transfer sound energy more quickly. sound waves travel faster through water because water is more dense than air. solids, like wood and metal, are very dense. therefore, sound waves travel fastest through these materials that have particles packed very tightly together. based on the passage, how does the speed of sound waves compare when people are talking underwater versus talking on the beach? the sound waves of people talking underwater move slower than the sound waves of people talking on the beach. the sound waves of people talking underwater move faster than the sound waves of people talking on the beach. the sound waves of people talking underwater and the sound waves of people talking on a beach cannot be measured. the sound waves of people talking underwater move at the same speed as the sound waves of people talking on the beach.

Explanation:

To solve this, we analyze the passage: it states sound waves travel faster through denser materials. Water is denser than air (beach air). So underwater (water) sound waves from talking should travel faster than on the beach (air). Let's check options:

• First option: Says underwater slower – wrong.
• Second option: Says underwater faster than beach – matches the analysis.
• Third option: Says can't be measured – passage doesn't support.
• Fourth option: Says same speed – wrong as water is denser than air, so speed differs.

Answer:

The sound waves of people talking underwater move faster than the sound waves of people talking on the beach.