Teargarten smiles. Andrea and her friend Daniella pay him no mind and whisper together.
“Young ladies,” he says, “do you know how to determine the height of a tall building with the aid of a barometer?” He holds one up.
“What a jerk!” says Andrea.
“Not entirely,” says Daniella.
“I don't know why you defend him.”
“It's my sense of things to come.”
Teargarten watches them whisper and scowls. “I wonder if that young lady can solve the problem for me.”
The teacher folds her arms and looks away in despair; she knows what's coming.
Daniella jerks her head at the guy to let Andrea know she's on.
Andrea looks at him. “Sure.”
“Stand up, Andrea,” says the teacher.
Andrea stands. “What's the problem?”
“We would like to determine the height of a tall building using no more than this.” He waves the barometer.
“You hang it by a string from the top of the building and lower it till it touches the ground. Then you measure the string.”
The other kids smile. They know Andrea. The teacher frowns.
Teargarten smiles patronizingly. “Well, I was hoping for an answer that would make use of the barometer as a barometer.”
“OK, you can walk up the stairs with it, hold it vertically to the wall and make a mark at the top every time, then as you come down count all the marks and you have the height of the building in barometer lengths.”
He tries to smile. “Yes, but what does that have to do with the barometer qua barometer?”
“OK, you could take it outside and measure the height of the barometer and the length of its shadow, and the length of the shadow of the building and by the use of proportion, you get the height of the building.”
The teacher nods to herself tragically.
Teargrten sours. “Doesn't really exploit the properties of the barometer, does it.”
“OK, tie it to the end of a string so it's a pendulum, go up to the top and swing it, calculate the value of ‘g’ at ground level, and also at the top of the building, using Newton's law of universal gravitation. From the difference of the two values you can get the height of the building.”
Teargarten is now afraid. He looks at the teacher, who shrugs. The kids are enjoying themselves.
The teacher says, “Yes, but the barometer, you see! Use the barometer!”
Teargarten is aghast. “Where did you learn this?”
“How old are you?”
“Nine point five seven eight three eight.”
The kids laugh. Teargarten and the teacher do not.
Andrea sighs with boredom. “I guess you want me say take barometric readings at the bottom and the top and calculate the height with them, but there's an easier way.”
Teargarten hardly dares ask. “What's that?”
The kids laugh. Teargarten and the teacher do not.
