( ... in deutsch)
 

... are asked: What is "pi"?
Mathematician: Pi is the ratio of the circumference of a circle to its diameter.
Physicist: Pi is 3.14159 plus or minus 0.000005
Engineer: Pi is about 3.

... were all given a red rubber ball and told to find the volume.
The mathmatician carefully measured the diameter and evaluated a triple integral.
The physicist filled a beaker with water, put the ball in the water, and measured the total displacement.
The engineer looked up the model and serial numbers in his red-rubber-ball table.

... were each placed in a room with a wooden table, a chair and a bucket of water, told to sit on the chair and the table set on fire.

The Engineer leapt up, ran to the bucket, picked it up and threw the water at the table, putting the fire out.

The Physicist got up, made some measurements, and then threw exactly the right amount of water over the fire so that it was put out, vapourising the water in the process, so the table was left dry.

The Mathematician got up, took out his notebook, looked at the burning table, looked at the bucket, made some calculations and said "Ah! A solution exists!" and sat down again, letting the table burn to a cinder.

A little while later the experiment was repeated, this time with the bucket of water placed on the table (they replaced the Mathematician's table).

The Engineer and Physicist did exactly the same as before.

The Mathematician looked at the table and bucket, then took the bucket off the table and put it on the floor, thereby reducing the problem to a previously solved one. He then sat down and let the table burn to a cinder again.

... are given an identical problem: Prove that all odd numbers greater than 2 are prime numbers. They proceed:

Mathematician: 3 is a prime, 5 is a prime, 7 is a prime, 9 is not a prime - counterexample - claim is false.
Physicist: 3 is a prime, 5 is a prime, 7 is a prime, 9 is an experimental error, 11 is a prime, ...
Engineer: 3 is a prime, 5 is a prime, 7 is a prime, 9 is a prime, 11 is a prime, ...

... when considering the behaviour of a howitzer:

A mathematician will be able to calculate where the shell will land
A physicist will be able to explain how the shell gets there
An engineer will stand there and try to catch it

An assemblage of the most gifted minds in the world were all posed the following question:

"What is 2 + 2 ?"

The engineer whips out his slide rule (so it's old) and shuffles it back and forth, and finally announces "3.99".

The physicist consults his technical references, sets up the problem on his computer, and announces "it lies between 3.98 and 4.02".

The mathematician cogitates for a while, oblivious to the rest of the world, then announces: "I don't know what the answer is, but I can prove an answer exists!".

... and a statistician are out hunting together. They spy a deer in the woods.

The physicist calculates the velocity of the deer and the effect of gravity on the bullet, aims his rifle and fires. Alas, he misses; the bullet passes three feet behind the deer. The deer bolts some yards, but comes to a halt, still within sight of the trio.

"Shame you missed," comments the engineer, "but of course with an ordinary gun, one would expect that."
He then levels his special deer-hunting gun, which he rigged together from an ordinary rifle, a sextant, a compass, a barometer, and a bunch of flashing lights which don't do anything but impress onlookers, and fires. Alas, his bullet passes three feet in front of the deer, who by this time wises up and vanishes for good.

"Well," says the physicist, "your contraption didn't get it either."
"What do you mean?" pipes up the statistician. "Between the two of you, that was a perfect shot!"

How they knew it was a deer:

The physicist observed that it behaved in a deer-like manner, so it must be a deer.

The mathematician asked the physicist what it was, thereby reducing it to a previously solved problem.

The engineer was in the woods to hunt deer, therefore it was a deer.

A Mathemetician (M) and an Engineer (E) attend a lecture by a Physicist.
The topic concerns Kulza-Klein theories involving physical processes that occur in spaces with dimensions of 9, 12 and even higher. The M is sitting, clearly enjoying the lecture, while the E is frowning and looking generally confused and puzzled.
By the end the E has a terrible headache. At the end, the M comments about the wonderful lecture. The E says "How do you understand this stuff?" M: "I just visualize the process" E: "How can you POSSIBLY visualize somrthing that occurs in 9-dimensional space?" M: "Easy, first visualize it in N-dimensional space, then let N go to 9"

Q. What do a mathematician, a physiscist and an engineer have in common?
A. They are all stupid, with the exception of the mathematician.

... are staying in a hotel while attending a technical seminar.
The engineer wakes up and smells smoke. He goes out into the hallway and sees a fire, so he fills a trashcan from his room with water and douses the fire. He goes back to bed.
Later, the physicist wakes up and smells smoke. He opens his door and sees a fire in the hallway. He walks
down the hall to a fire hose and after calculating the flame velocity, distance, water pressure, trajectory, etc. extinguishes the fire with the minimum amount of water and energy needed.
Later, the mathematician wakes up and smells smoke. He goes to the hall, sees the fire and then the fire hose. He thinks for a moment and then exclaims, "Ah, a solution exists!" and then goes back to bed.

In the high school gym, all the girls in the class were lined up against one wall, and all the boys against the opposite wall.
Then, every ten seconds, they walked toward each other until they were half the previous distance apart.  A mathematician,
a physicist, and an  engineer were asked, "When will the girls and boys meet?"

The mathematician said: "Never."

The physicist said: "In an infinite amount of time."

The engineer said: "Well... in about two minutes, they'll be close enough for all practical purposes."

... went to the races one Saturday and laid their money down. Commiserating in the bar after the race, the engineer says, "I don't understand why I lost all my money. I measured all the horses and calculated their strength and mechanical advantage and figured out how fast they could run . . ."
The physicist interrupted him: ". . . but you didn't take individual variations into account. I did a statistical analysis of their previous performances and bet on the horses with the highest probability of winning . . ."
". . . so if you're so hot why are you broke?" asked the engineer. But before the argument can grow, the mathematician takes out his pipe and they get a glimpse of his well-fattened wallet. Obviously here was a man who knew something about horses.
They both demanded to know his secret. "Well," he says, between puffs on the pipe, "first I assumed all the horses were identical and spherical . . ."

... all have to nip to the loo.
The Mathematician has a leak, and then sprinkles a few drops of water on his hands, turns to the attendant and says 'Mathematicians learn to be concise'.
The Physicist has a turn, spends 5 minutes scrubbing his hands, then turns to the attendant and says 'Physicists learn to be thorough'.
The engineer has a wee, doesn't bother washing his hands, turns to the attendant and say 'Engineers learn not to pee all over their hands'.

... are each given 50 pounds to measure the height of a building.
The mathematician buys a ruler and a sextant, and by determining the angle subtended by the building a certain distance away
from the base, he establishes the height of the building.
The physicist buys a heavy ball and a stopwatch, climbs to the top of the building and drops the ball. By measuring the time it
takes to hit the bottom, he establishes the height of the building.
The engineer puts forty pounds into his pocket. By slipping the doorman the other ten, he establishes the height of the building.

Three professionals, a mathematician, a physicist and an engineer, took their final test for the job. The sole question in the
exam was "how much is one plus one".
The math dude asked the receptionist for a ream of paper, two hours later, he said: I have proven its a natural number.
The physicist, after checking parallax error and quantum tables said: Its between 1.9999999999, and 2.0000000001
The engineer quicly said: oh! its easy! its two,.... no, better maake it three, just to be safe.

links:

http://www.xs4all.nl/~jcdverha/scijokes/6.html
http://www.workjoke.com/projoke.htm
http://www.maths.warwick.ac.uk/~uwms/fun/mathjoke.html