3. Sound travels faster through warm materials than cold materials because A. warm particles move slowly B. gas particles are packed tightly C. warm particles are moving quickly D. sound does not travel faster through a warm substance 4. Ships use echolocation to measure the A. size of fish B. area of ocean C. depth of water D. density of water 5. When the direction of a wave changes as it passes from one medium to another, it is caled A. Density C. Reflection B. Echo D. refraction 6. What happens to the speed of sound when it travels in warmer objects? A. Constant B. Fastar C. Slower D. cannot be determine 7. When a boy yells his name inside a cave, the sound reflects off the walls of the cave and travels back to his ears. What do you call the reflected sound? A. Density B. Echo C. Echolocation D. refraction 8. What is the reason for hearing noises in the distance while standing near a body of water during nighttime? A. There are fewer noises at night. B. Water conducts sound better at night. C. Sound bounces off water better at night. D. Sound waves are bent towards the cool air over the water. 9. Concerts usually take place during nighttime where everyone has a chance to see and to enjoy the live show. Why does sound contribute to the concert schedule? A. Sound is more audible at night due to minimal noise. B. Sound propagates faster in air at night than at daytime. C. Sound is heard well in far areas during nighttime than during daytime. D. Sound changes and refracts when it encounters a medium of different density 10. Which is quieter, a room with hanging curtains or one with bare concrete walls? Why? A. Both rooms have the tendency to be peaceful and to be quiet depending on the location. B. It is quieter in a room with concrete walls because sound travels faster in medium with the higher elastic property at the molecular level. C. It is quieter in a room with curtains because the bare concrete wall brings about multiple reflections of sound. D. It is quieter in a room with bare walls because hanging curtains enhance the effect of sound reverberation.
