The Student and The Barometer

Some time ago I received a call from a colleague. He was about to give a student a zero for his answer to a physics question, while the student claimed a perfect score. The instructor and the student agreed to an impartial arbiter, and I was selected.

I read the examination question: "Show how it is possible to determine the height of a tall building with the aid of a barometer." The student had answered: "Take the barometer to the top of the building, attach a long rope to it, lower it to the street, and then bring it up, measuring the length of the rope. The length of the rope is the height of the building."

The student really had a strong case for full credit since he had really answered the question completely and correctly! On the other hand, if full credit were given, it could well contribute to a high grade in his physics course and certify competence in physics, but the answer did not confirm this.

I suggested that the student have another try. I gave the student six minutes to answer the question with the warning that the answer should show some knowledge of physics. At the end of five minutes, he hadn't written anything. I asked if he wished to give up, but he said he had many answers to this problem; he was just thinking of the best one. I excused myself for interrupting him and asked him to please go on.

In the next minute, he dashed off his answer, which read: "Take the barometer to the top of the building and lean over the edge of the roof. Drop the barometer, timing its fall with a stopwatch. Then, using the formula x=0.5*a*t^2, calculate the height of the building." At this point, I asked my colleague if he would give up. He conceded, and gave the student almost full credit.

While leaving my colleague's office, I recalled that the student had said that he had other answers to the problem, so I asked him what they were. "Well," said the student, "there are many ways of getting the height of a tall building with the aid of a barometer. For example,if the sun is shining you could measure the height of the barometer, then set it on end and measure the length of its shadow. Then you measure the length of the skyscraper's shadow, and thereafter it is a simple matter of proportional arithmetic to work out the height of the skyscraper.

"Fine," I said, "and others?"

"Yes," said the student, "there is a very basic measurement method you will like. In this method, you take the barometer and begin to walk up the stairs. As you climb the stairs, you mark off the length of the barometer along the wall. You then count the number of marks, and this will give you the height of the building in barometer units." "A very direct method."

"Of course. If you want a more sophisticated method, you can tie the barometer to the end of a string, swing it as a pendulum, and determine the value of g [gravity] at the street level and at the top of the building. From the difference between the two values of g, the height of the building, in principle, can be calculated."

"On this same tack, you could take the barometer to the top of the building, attach a long rope to it, lower it to just above the street, and then swing it as a pendulum. You could then calculate the height of the building by the period of the precession".

"Finally," he concluded, "there are many other ways of solving the problem. Probably the best," he said, "is to take the barometer to the basement and knock on the superintendent's door. When the superintendent answers, you speak to him as follows: 'Mr. Superintendent, here is a fine barometer. If you will tell me the height of the building, I will give you this barometer."

At this point, I asked the student if he really did not know the conventional answer to this question. He admitted that he did, but said that he was fed up with high school and college instructors trying to teach him how to think.

The name of the student was Niels Bohr, who later received the Nobel prize for Physics.

How To Annoy People In An Elevator
How To Annoy People In An Elevator ===================================== Meow or bark occasionally.Push the buttons & pretend they give you a shock. Smile & go back for more.Greet everyone who comes in the elevator with a big handshake.Walk on with a cooler that says "human head" on the side.Give a play-by-play account of a person's every action.Recite poetry to everyone you meet.Lean against the button panel.Get two cell phones and talk to yourself on them.Scream the floor number as you pass it.Floss your teethBring a portable DVD player and watch your favorite movie with the volume on highStare at another passenger for a while, then announce "You're one of THEM!" and move to the far corner of the elevator.Announce in a demonic voice: "I must find a more suitable host body."Claim that you must always wear a bicycle helmet as part of your "astronaut training."Start a sing-a-long.Listen to the elevator walls with a stethoscope.Drop a bag of groceries and look around like it was the other peoples fault.Frown and mutter "gotta go, gotta go" then sigh and say "oops!"Hold the doors open and say you are waiting for a friend. After awhile, let the doors close and say "Hey Greg, How's your day been?"Inform everyone you meet of your personal Kennedy assassination, UFO, and OJ Simpson conspiracy theories.When arriving at your floor, grunt and strain to yank the doors open, then act embarrassed when they open by themselves.Blow your nose and offer to show the contents of your tissue to other passengers.Grab a pillow and attempt to fall asleepMake race car noises when anyone gets on or off.Wear a puppet on your hand and use it to talk to other people.Shadow box.Stand really close to someone and sniff them occasionally.Make beeping noises when a large person backs up.Face the corner and don’t moveDemand that everyone address you as "Conquistador."Call a girl a dude.Stand silent and motionless in the corner, facing the wall, without getting off.If anyone brushes against you, recoil and holler "Bad touch!"Call out, "Group Hug!" & then enforce it.Whenever someone steps in the elevator in a deep voice say, "GET OUT!"Bring a camera & take pictures of everyone on the elevator.Sing the 99 bottles of beer song.Pretend you are selling something in an infomercial.Ask if you can push the button for the other people and push the wrong ones.When the doors close, announce to the others, "It's ok! Don't panic, they will open again!"Swat at flies that aren't there.Inform others that they exist only in your imagination.Break dance to elevator music.Have a fake obnoxious cell phone conversationPretend you're invisibleLay out a small blanket and some food to have a picnicMurmur and/or talk to yourselfDraw a little square on the floor with chalk and announce to the other passengers that this is your "personal space."Holler "Chutes away!" whenever the elevator descends.Take a bite of a sandwich and ask another passenger: "Wanna see wha in muh mouf?"One word: Flatulence!Stomp on little plastic ketchup packets.Play the harmonica.When the elevator dings, scream.Stare at your thumb and say, "I think it is getting larger!"Stare, grinning, at another passenger for a while, and then announce: "I've got new socks on!"Crack open your briefcase or purse, and while peering inside ask: "Got enough air in there?"Pick your ear wax.Scratch your head excessivelyWalk on making dinosaur noises and nudge people with your nose.Say “ding” every time you reach a new floorPut powdered sugar in your hair and scratch your head a lot.Insist completely ridiculous things are true - like Bush is still President.Sell Girl Scout cookies.Leave a box between the doors.Walk around with a plastic sword and shield and tell strangers "I must avenge the death of my father."Pull your gum out of your mouth in long strings.Wear "X-Ray Specs" and leer suggestively at other passengers.Drop and pen & wait until someone goes to pick it up and then scream "NOOO THAT'S MINE!"Repeat the following conversation a dozen times: "Do you hear that?", "What?", "Never mind, it's gone now."Tie bells to all your clothes.Sing really off pitch to a popular song.Set up a chair and desk in the elevator, and whenever anyone gets on, say, "Hello! Welcome to my office. Do you have an appointment?"Sway from side to side the whole ride.Gasp, look and point up. See how many people look.Blow spit-bubbles.Ask each passenger getting on if you can push the button for them.Grimace painfully while smacking your forehead and muttering "Shut-Up, all of you, just shut up!"Rock back and forth while sucking on your thumbFake cough/sneeze uncontrollablyCall McDonald's and try to make a reservation for that evening.Burp, and then say "mmmm...tasty!"Make explosion noises when anyone presses a button.Bring a Twister mat and ask if people want to play.When you get to your floor try and open the doors yourself and act embarrassed when they open by themselves.Call the Psychic Hotline from your cell phone and ask if they know what floor you are on.Bring a chair along.Ask people what gender they are.Moan "Oh no! Not now! Damn motion sickness!"Whistle the first seven notes of "It's a Small World" over and over again.Insist to a stranger that you're relatedOffer name tags to everyone getting on the elevator. Wear yours upside-down.Drum on every available surface.Act drunk.Do Tai Chi exercises.