Here's a Question! - Ice in a Glass
Ice is added to a glass of water so that the ice floats freely. What happens to the level of the water when the ice melts?
Announcer: Frostbite Theater presents... Cold Cuts! No baloney!
Joanna and Steve: Just science!
Joanna: Hi! I'm Joanna!
Steve: And I'm Steve!
Joanna: Here's a question for you...
Steve: Ice is added to a glass of water so that the ice floats freely.
Joanna: What happens to the level of the water when the ice melts?
Steve: Does the level rise?
Joanna: Does the level fall?
Steve: Does the level fall at first, and then rise?
Joanna: Or, does the level stay the same?
Pause the video now if you'd like to think it over before we show you what happens.
Steve: An object floats because it displaces a volume of liquid with a weight that's equal to the weight of the object. The ice cubes are floating, so they're displacing their weight in liquid water.
Joanna: They also make their weight in liquid water when they melt. It doesn't matter if some of the water is solid and some of the water is liquid. The level of the water in the glass stays the same because the amount of water in the glass stays the same.
Thanks for watching. I hope you'll join us again soon for another question!
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