Can you Hear the Difference between Hot & Cold Water?

Intro:

Welcome to daily fun facts where we discuss fun facts about this crazy world. Use these newfound facts to break the ice and start an interesting conversation.  Happy learning everyone!

Dialogue:

Brie: What a cold and gloomy winter this has turned out to be! I’ve been watching this commercial for Twinings® Tea, and it’s making me want a cup of hot tea right now. The sound that the hot water makes as it’s being poured into the glass makes the tea seem so warm and enticing. 

Andrea: I agree, we’ve had a real cold spell this winter.  The creators of that tea ad you’ve been watching crafted those sensory sounds to remind people of what it’s like to boil a cup of light, stimulating, and aromatic tea .  Obviously, they were quite successful in their delivery!

Brie: Indeed! I wonder how they managed to do that? The commercials must have stimulated the connection between my sense of hearing and brain.

Andrea:  You are right, Brie! That commercial is successful because it mixes brain science with auditory and multisensory product branding and marketing.  There has been a lot of research that shows that we tie sounds to memories. For example, think of the nostalgia you feel when you hear a song on the radio that reminds you of a cherished moment in your life.   In this ad, the sound of pouring hot water triggers in me a pleasant memory of brewing a fragrant cup of hot tea! 

Brie:  What do you mean by the sound of pouring hot water?  It’s obvious by looking at the steam that the water is hot, but how can you tell based on the sound? 

Andrea: Hot water has its own characteristic sound, which, I must say, is quite an interesting fun fact!  Did you know that by pouring water into a cup, people are able to tell if the water is hot or cold based only on a slight difference in sound? The sound differences are subtle but definitely distinguishable if you pay close attention.  You need to have a good sense of hearing to perceive the difference.

Brie:  热水和冷水倒入杯中产生的声音是有细微差别的。如果我们在平时生活中用心倾听，就可以只依靠倒水声音的不同来能辨别水是冷是热了！ Interesting！What is the reason for the difference in sound between hot and cold water?

Andrea:  The reason that hot and cold water sound different when poured into a cup is due to their differing viscosities.  Viscosity is a measure of the resistance of a fluid to change shape and is defined by the internal shear stress between molecules rubbing against each other.  Hot water has a lower viscosity than cold water because heat causes the molecules to become excited and energized. Cold water molecules, on the other hand, are slower moving and tend to stick to one another more.  As the temperature of a fluid increases, its viscosity decreases.  Just think of honey: As it gets warmer, it becomes more runny.  As a result of these differences in viscosity, when cold water is poured into a cup, the splashes that it makes against the sides of the cup sound different than the splashes that hot water makes.  The more we practice listening when we pour hot and cold water, the more attuned our brain becomes to the differences in sound.   

Brie:  倒热水和冷水声音的不同跟它们粘度的不同有关。粘度是流体抵抗变形能力的一个量度，是由分子之间的内部摩擦来定义的。随着水温的逐渐升高，水的粘度是逐渐降低的。由于热水的粘度低于冷水，当将冷水倒入杯中时，其在杯壁上产生的飞溅声与热水产生的飞溅声是不同的。So, what kind of sounds do hot and cold water make when poured?

Andrea:  Hot water produces a sound that has a higher pitch than cold water due to the faster movements of hot water molecules. Since it is more viscous, cold water produces fewer bubbles than hot water when it is poured.  This causes cold water to produce a lower frequency sound. 

Brie:  由于热水的水分子处于更活跃的运动状态，并且热水含有更多的气泡，向空杯中倒热水声的音调是高于倒冷水声的音调的。 Why don’t we go outside and practice listening to test this out?  I will get a big bathtub and pour either hot water or cold water into it.  I will blindfold you and then you can get in the tub and listen to try to figure out whether I’m pouring in the hot water or the cold water!

Andrea:  Ha, very funny Brie, but that’s not exactly my cup of tea!  With your method, I don’t need to have a good sense of hearing to figure out the difference in temperature!  I’ll be able to tell immediately, thanks to a different sense:  My sense of touch!  I think you should be the one to get into the tub!

Brie:  Oh come on, I thought that was a good joke! I don’t want to get in a tub out where it’s freezing cold either, so that’s also not my cup of tea! 

Close:

So, everyone, there’s your fun fact of the day!  Let’s go over some of the vocabulary and phrases from this dialogue.

Vocabulary:

Twinings® Tea  唐宁茶，茶的一个品牌

Stimulating  / ˈstɪmjʊˌleɪtɪŋ /  使增强活力的，促进身体机能的

Aromatic  / ˌær əˈmæt ɪk /  芳香的，有香气的

Auditory  / ˈɔ dɪˌtɔr i /  听觉的

Nostalgia  / nɒˈstæl dʒə /  怀旧感

Fragrant  / ˈfreɪ grənt /  芳香的

Characteristic  / ˌkær ɪk təˈrɪs tɪk /  特点，特色

Distinguishable  / dɪˈstɪŋ gwɪʃə bəl /  可分辨的

Viscosity  / vɪˈskɒs ɪ ti /  粘度

Resistance  / rɪˈzɪs təns /  阻力

Shear stress  / ʃɪər  strɛs /  剪切应力

Attune  / əˈtun /  调和

Phrases:

Cold spell  一段时间的寒冷天气

Not (someone’s) cup of tea 不符合某人的喜好

Alright, join us next time for another fun fact to help break the ice! 好了，这就是我们今天的有趣常识分享，如果喜欢我们，请别忘了点击订阅！拜拜，咱们下期再见！

Disclaimer: This podcast is not sponsored by nor has any affiliation with the Twinings® Tea company. 

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