"Ричард Фейнман. Surely You're Joking, Mr. Feynman!/Вы, конечно, шутите, мистер Фейнман! (англ.)" - читать интересную книгу автора

don't know what he'll convince me of tomorrow!"
I'll tell you an argument that will make you think it's one way, and
another argument that will make you think it's the other way, OK?
One argument is that when you're sucking water in, you're sort of
pulling the water with the nozzle, so it will go forward, towards the
incoming water.
But then another guy comes along and says, "Suppose we hold it still
and ask what kind of a torque we need to hold it still. In the case of the
water going out, we all know you have to hold it on the outside of the
curve, because of the centrifugal force of the water going around the curve.
Now, when the water goes around the same curve the other way, it still makes
the same centrifugal force toward the outside of the curve. Therefore the
two cases are the same, and the sprinkler will go around the same way,
whether you're squirting water out or sucking it in."
After some thought, I finally made up my mind what the answer was, and
in order to demonstrate it, I wanted to do an experiment.
In the Princeton cyclotron lab they had a big carboy - a monster
bottle of water. I thought this was just great for the experiment. I got a
piece of copper tubing and bent it into an S-shape. Then in the middle I
drilled a hole, stuck in a piece of rubber hose, and led it up through a
hole in a cork I had put in the top of the bottle. The cork had another
hole, into which I put another piece of rubber hose, and connected it to the
air pressure supply of the lab. By blowing air into the bottle, I could
force water into the copper tubing exactly as if I were sucking it in. Now,
the S-shaped tubing wouldn't turn around, but it would twist (because of the
flexible rubber hose), and I was going to measure the speed of the water
flow by measuring how far it squirted out of the top of the bottle.
I got it all set up, turned on the air supply, and it went "Puup!" The
air pressure blew the cork out of the bottle. I wired it in very well, so it
wouldn't jump out. Now the experiment was going pretty good. The water was
coming out, and the hose was twisting, so I put a little more pressure on
it, because with a higher speed, the measurements would be more accurate. I
measured the angle very carefully, and measured the distance, and increased
the pressure again, and suddenly the whole thing just blew glass and water
in all directions throughout the laboratory. A guy who had come to watch got
all wet and had to go home and change his clothes (it's a miracle he didn't
get cut by the glass), and lots of cloud chamber pictures that had been
taken patiently using the cyclotron were all wet, but for some reason I was
far enough away, or in some such position that I didn't get very wet. But
I'll always remember how the great Professor Del Sasso, who was in charge of
the cyclotron, came over to me and said sternly, "The freshman experiments
should be done in the freshman laboratory!"


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Meeeeeeeeeee!


On Wednesdays at the Princeton Graduate College, various people would
come in to give talks. The speakers were often interesting, and in the