Sound is a form of energy that is produced by vibrations. These vibrations create waves that travel through mediums such as air, water, or solids. The study of sound is known as acoustics.
Properties of Sound
Amplitude: The height of a sound wave, which determines its loudness.
Frequency: The number of vibrations per second, which determines the pitch of the sound.
Wavelength: The distance between two consecutive compressions or rarefactions in a sound wave.
When an object vibrates, it creates sound waves that travel outward in all directions. These wavescause the particles in the surrounding medium to vibrate, transmitting the sound energy from the source to our ears.
How We Hear Sound
When sound waves reach our ears, they cause the eardrum to vibrate. These vibrations are then transmitted through the tiny bones in the middle ear to the cochlea in the inner ear, where they are converted into electrical signals that are sent to the brain and interpreted as sound.
Explore objects that can be manipulated in order to determine cause-and-effect relationships (e.g., distance between objects affecting strength of a force, orientation of magnets affecting direction of a magnetic force) of electric interactions between two objects not in contact with one another (e.g., force on hair from an electrically charged balloon, electrical forces between a charged rod and pieces of paper) or magnetic interactions between two objects not in contact with one another (e.g., force between two permanent magnets or between an electromagnet and steel paperclips, force exerted by one magnet versus the force exerted by two magnets).
Apply scientific ideas about magnets to solve a problem through an engineering design project (e.g., constructing a latch to keep a door shut, creating a device to keep two moving objects from touching each other such as a maglev system).