Learning Objectives

The purpose of sirens, alarms, and bells in warning systems is to:

• alert people to danger

• decorate the environment

• play music

• provide entertainment

In which of the following areas are audible sounds essential?

• Cooking

• Music

• Painting

• Gardening

What technology uses high-frequency inaudible sound waves to clean delicate items like jewelry and watches?

• Ultrasonic cleaning

• Laser cleaning

• Steam cleaning

• Chemical cleaning

Physics: Sound travels through different mediums such as air, water, and solids by:

• vibrating the particles in the medium

• changing the temperature of the medium

• altering the chemical composition of the medium

• creating a vacuum in the medium

Inaudible sounds are sounds that:

• can be heard by humans

• cannot be heard by humans

• are always loud

• are always soft

What are audible sounds?

• Sounds that humans cannot hear

• Sounds that humans can hear, such as talking, clapping, or a dog barking

• Sounds that only animals can hear

• Sounds that are only produced by musical instruments