Interesting and Humour - page 2694

[Konstantin Gruzdev]

Александр:

Two identical boats are approaching the jetty. Both boaters are pulled up with a rope. The opposite end of the rope of the left boat is tied to a bollard on the pier; the opposite end of the rope of the right boat is in the hands of the sailor on the pier, who also pulls the rope towards himself. All three of them exert the same effort and act in perfect synchrony.

Which boat will moor faster?

Left? Right? Simultaneously?

The left boat will moor faster. The sailor on the shore works like a spring, so some of the pulling energy of the right-hand boatman will be lost in that sailor's knee, eye and mat muscles.

[Alexandr Bryzgalov]

the right one is faster, if you remove everything and leave only the points, then the right points will approach each other faster than the left ones.

The points are the contact points between the sailors' hands and the rope, and the stump on the shore.

In other words, the boats are in different frames of reference.

physics 6-9 grade

[Vladimir Belev]

What if the forces acting on the rope and on the boats were decomposed into vectors?

[Dmitry Fedoseev]

If the picture is used to illustrate the theme of Newton's third law, the boats will move at the same speed.

If used as an illustration of Newton's third law, the boats will move at twice the speed because the two sailors will do the same work twice as fast.

[[Deleted]]

how much you can think.... there are two sailors in the right picture... the one on the pier will still fall in the water=) so boat number one will come first =)

[Vladimir Karputov]

Roman Busarov:
how much you can think.... there are two sailors in the right picture... the one on the pier will fall in the water anyway =) so boat number one will come first =)

Original solution :) And, by the way, has the right to life, as the conditions of the problem does not specify the degree of intoxication sailor on shore and how firmly he is on his feet.

[pavlick_]

Dmitry Fedoseev:

If the picture is used to illustrate the theme of Newton's third law, the boats will move at the same speed.

If used as an illustration of Newton's third law, the boats will move at the same speed, because the two sailors will do the same work twice as fast.

The condition of the problem determined the force equal between the three sailors, so they will arrive equally. If we repeat the experience in reality, the right-hand boat will arrive faster, because the sailor on the left and the sailors on the right will not be able to apply the same effort, because a man cannot accelerate the pace of pulling the rope forever, and the sailors on the right have twice the potential (the rope is tightened from both sides).

[Alexandr Murzin]

Not a complete condition, it does not say whether the anchors are down.

[Pavel Gotkevitch]

Александр:

Two identical boats are approaching the jetty. Both boaters are pulled up by a rope. The opposite end of the rope of the left boat is tied to a bollard on the wharf; the opposite end of the rope of the right boat is in the hands of the sailor on the wharf, who also pulls the rope towards himself. All three of them exert the same effort and act in perfect synchrony.

Which boat will moor faster?

Left? Right? Simultaneously?

Puzzling mechanics - Perelman J.I.

/go?link=http://www.booksshare.net/index.php?id1=4&category=mechanics&author=pereliman-ya-i&book=1933&page=7

[[Deleted]]

Pavel Gotkevitch:

Puzzling mechanics - Perelman J.I.

/go?link=http://www.booksshare.net/index.php?id1=4&category=mechanics&author=pereliman-ya-i&book=1933&page=7

Well, I didn't let people have a brainwave.