How long is the tire cross wrench better to use

According to the Across wrench principles of physics, the longer the tire cross wrench lever is, the more labor-saving. In actual use, the appropriate length should be selected so that it is easy to use.We all know that Archimedes once said: "Give me a foothold and a lever long enough, and I can move the earth." However, while defending the ancient city of Syrah, he rushed to several people.

The soldier who used the lever to move the stone yelled: "Don't use such a long lever for a short one." Why is this? The soldiers were stunned. How can I use short leverage? Don't you need to work hard? But the king commanded: Believe everything Archimedes has said, and have to do what he believes and disbelieve, and it saves more effort than using a long lever. The soldiers were puzzled and prepared to consult Archimedes afterwards.

Unfortunately, because the castle was broken by the enemy, Archimedes was killed by Roman soldiers before he could answer the questions of the soldiers.It turns out that when we usually study levers, we mainly focus on light levers, that is, without considering the lever's own weight, so the longer the lever, the larger the power arm can be adjusted to save effort. But when the leverage is considered, the situation has changed. We will illustrate it through typical data calculations.