From the brains behind brains on, this is the moment of um.

Moment of um comes to you from APM Studios. I'm Hortensia Hippopotamus.

Oh, what a perfect day for some pool time.

As a hippopotamus living at the zoo, I've got a gorgeous habitat, complete with lovely grassy hills,

a few tree trunks for backscratches, and a big, glorious pool.

You may think I'm quite the hippopampered hippopotamus, but I work for a living.

You think it's easy being a huge, gorgeous creature like me?

I'm on my feet for at least an hour every day, strutting my stuff for the fans that come to visit me, and these tutsies of mine support all three thousand pounds of

me. That's like the weight of a car. So when it's time for this hippo Hottomus to cool down and relax, I slip into my pool and the water lifts all my cares away.

But also my body literally feels lighter when I'm doing my splishy-splashy self-care.

Why is that?

My human friend Rebecca wanted to know too. Why do things seem lighter in the pool?

Hi, hello. My name is Chechen. I am an associate professor here at Caltech in the physics department.

And the answer to that is, well, water is helping you. Water is doing the job of holding things up.

So imagine you have a rubber duck in your hand. And if you're standing on the ground, you let go of the rubber duck, the rubber duck would fall to the ground. Right? But if you're standing in the pool and you let go of the rubber duck, the rubber duck would float on the surface of the water.

And even if you pull the rubber duck beneath the water surface, it will pop up to the surface.

So that's because, flotation.

Because water is holding things up. Of course, we are much heavier than the rubber duck.

So when we are in the water, we do not automatically just float on the surface,

but water is still doing some of the work to hold us up.

And actually, if you go somewhere in the Mediterranean, there's a place called the Dead Sea.

And the Dead Sea,

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