Why Can't We Hear a Dog Whistle?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why can't we hear a dog whistle?

The Big Idea

We cannot hear a dog whistle because it makes sounds above 20,000 hertz! That is higher than humans can hear. Dogs hear much higher pitches, so they notice it easily.

Very High Pitch

Step one: a very high pitch. A dog whistle makes sounds above 20,000 hertz. Sound that high is called ultrasound, which means beyond normal hearing.

Humans Miss It

Step two: humans miss it. People hear from about 20 to 20,000 hertz. Anything above that is silent to us, even though the air really is vibrating.

Dogs Hear It

Step three: dogs hear it. Dogs can hear pitches up to about 45,000 hertz, thanks to their special ears. So they can notice the whistle while we hear nothing.

A Closer Look

Let's take a closer look! People hear up to about 20,000 hertz. Dogs hear up to about 45,000 hertz. A dog whistle sits above our range, in the ultrasound zone. Bats use even higher sounds to find food in the dark.

Quick Facts

Quick facts! Our hearing range also shrinks a little as we get older. Bats and dolphins use ultrasound to find things. Ultrasound machines can even take pictures of babies before they are born. Only use a dog whistle gently, and never blow it near anyone's ears.

Think Like a Scientist

Now, detective task! Draw a number line from 0 to 60,000 hertz. Mark where people hear, from 20 to 20,000, and where a dog hears. Where would you put a dog whistle? Share what you discover with a grown-up.

Outro

Some sounds are real, but too high for us. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!