Rusted bolts
We use a wrench to turn nuts on bolts because they require less force. Consider a hexagonal nut in diameter. We can tighten this nut with one of two wrenches, wrench A with lever arm and wrench B with lever arm . Both wrenches have a very small mass, so you may neglect their masses in this problem. What is the ratio of the total work it would take to tighten the nut one full turn with wrench A to the total work it would take with wrench B?
The answer is 1.
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Come to think of it, this is actually a trick question of sorts. WORK DONE would be the same for both wrenches as the nut would create the same moment. The difference lies in the amount of FORCE needed. Do not confuse the question with the ratio of the FORCE needed to tighten the nut with wrench A to the FORCE needed to tighten the nut with wrench B. The answer would have been 2 since in wrench A, the applied force only travels half the distance as compared to wrench B. It is the FORCE which varies, not the WORK DONE.