An example problem from today's lecture:
A sleep-deprived parent is warming a bottle for a midnight feeding. He places a bottle containing 250 ml of infant formula at 275K into 300 ml of water at 320 K. When the two liquids reach equilibrium, what is the temperature of the formula?
Answer: Trick question! While the bottle is warming, he dozes off holding the baby, and by the time they wake up, both bottle and water have cooled to only 288K.
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For extra credit, explain exactly *how* sound attenuates between baby and parent in order to allow this seemingly-impossible feat of returning to sleep in the presence of hungry toddler :).
That's neurophysics, actually. As the parent of (fortunately now grown) premature twins, I can assure you that it's possible to get so sleep-deprived that even stereo screams centimeters from the ear won't wake you. Also, babies crying are more effective than anything the CIA ever dreamed of in terms of keeping people awake for weeks on end.
or, you could have asked:
What is the formula for temperature?
Ha!
Any response in class to the use of "infant formula" in your example? 'Ware the lactivistas!...
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In 2002, there was a report that the military had deployed a sound system to Afghanistan that directed very loud noise into caves. Among the sound effects: a crying baby...
It's either too hot or too cold.
The trivial solution is to supply milk in its natural 310 K containers (that happen not to be soybeans - look at the formula contents label). That allows the physicist to sleep near term (but in anticipation of being bankrupted by pantihose purchases long term).
That depends on the spin state of the physicist, doesn' tit?
Also, after drinking the formula, what temperature will the baby be? (Assume a spherical baby.)
I feel grateful that my kids' milk was kept in the 310K containers described by Uncle Al (which work perfectly well even if the physicist - or, in my case, the mathematician - is asleep).
Your esercise is brilliant, I wish more science for everyday life was taught to non-science majors everywhere.
What is the material and mass of the bottle?
Prepare to be tired for five years. Or maybe that's just for single mothers. The one time I tried going to a concert, I fell asleep and woke only when trumpets sounded.
To prevent mother stress burnout or divorce, give Kate a day off every week.