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cols[1].querySelector("a") : null; var item = { name: textOf(nameLink || cols[0]), mappedTo: textOf(fileLink || cols[1]), quantity: cols[2] ? textOf(cols[2]) : "" }; if (item.name) { items.push(item); } } return items; } function fillFromAccordion(accordion) { if (!accordion) { return; } var versucheStep = accordion.querySelector('[data-step="versuche"]'); var versuche = parseItemBlocks(versucheStep, false); setHeadline("print-versuche", stepTitle(versucheStep)); fillTable("print-versuche", versuche, false); var lieferumfangStep = accordion.querySelector('[data-step="lieferumfang"]'); var lieferumfang = parseItemBlocks(lieferumfangStep, true); fillTable("print-lieferumfang", lieferumfang, true); var zubehoer = accordion.querySelector('[data-step="zubehoer"]'); var sections = zubehoer ? zubehoer.querySelectorAll(".card-body") : []; var notwendig = []; var empfohlen = []; for (var i = 0; i < sections.length; i++) { var items = parseItemBlocks(sections[i], false); if (sections[i].querySelector(".text-red, .icon-warning-black")) { notwendig = items; } else if (sections[i].querySelector(".text-green, .icon-Mehrwert_black")) { empfohlen = items; } } fillTable("print-zubehoer-notwendig", notwendig, false); fillTable("print-zubehoer-empfohlen", empfohlen, false); var mediaStep = accordion.querySelector('[data-step="media"]'); var media = parseMedia(mediaStep); setHeadline("print-media", stepTitle(mediaStep)); fillTable("print-media", media, true); } function start() { var itemUrl = resolveItemUrl(); if (!itemUrl) { setTimeout(function () { window.print(); }, 2000); return; } loadAccordion() .then(function (accordion) { fillFromAccordion(accordion); }) .catch(function (err) { if (window.console && console.warn) { console.warn("Accordion konnte nicht geladen werden:", resolveItemUrl(), err); } }) .then(function () { setTimeout(function () { window.print(); }, 500); }); } if (document.readyState === "loading") { document.addEventListener("DOMContentLoaded", start); } else { start(); } })();
 

Technical data


Velocity-independent and velocity-dependent friction (eddy current damping) with Demo-Track and Timer 4-4

Article no: P1198105
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> Principle

Friction slows every movement. The aim of this experiment is to demonstrate the influence of friction and the difference between various types of friction by way of a demonstration track and a cart that performs a decelerated motion. The friction between a piece of felt and a metal surface is an example of kinetic friction (sometimes also called sliding friction or dynamic friction). The frictional force in the case of kinetic friction is independent of the velocity of the motion. The friction that is caused by an eddy current brake, on the other hand, is an example of a velocity-dependent frictional force. In this case, it is proportional to the velocity.

Benefits

  • Accurate results due to measurements with low friciton: cart with sapphire bearings
  • Over the entire track length adjustable feet for a very simple alignment of the track even on small tables
  • Extrem robust accessories, for example no overloading of cars due to elastic bearing of base plate, prevent unnecessary breakdowns
  • Timer 4-4 can be used for almost every experimental requirement : distance-time law for four tracks, measurement of speed at four positions, principles of collisions, measurement of the orbiting time of a rotary movement, the direct measurement of the duration of a complete swing of a mechanical pendulum and for short or long-term measurements with two 8-digit displays by connecting each of 2 timers

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