Ultrasonics

Okay little one, do you know what sound is? It's when something vibrates, like your voice when you talk or when you clap your hands together. You can hear some sounds, like music or people talking, but some sounds are too high or too low for us to hear. Those are called "ultrasonic" sounds.

Scientists and engineers use ultrasonic sounds for all sorts of things. They use special machines that send out ultrasonic sound waves and then listen for them to bounce back. They can tell how far away something is based on how long it takes for the sound to bounce back.

One really cool use of ultrasonics is in medical imaging. If a doctor wants to see inside your body, they can use an ultrasound machine to send sound waves through your skin and into your body. The sound waves bounce off your organs and bones and the machine turns that information into an image that the doctor can see. It's like taking a picture inside your body!

Ultrasonics are also used in cleaning. If you've ever been to the dentist, you've probably had your teeth cleaned with a tool that uses ultrasonic vibrations to shake loose plaque and tartar. There are also machines that use ultrasonics to clean jewelry and other small items.

So even though we can't hear ultrasonic sounds, they are very important and useful for lots of things!