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要想分析影响机械效率大小的因素,就是要找到影响有用功和额外功大小的因素。要想计算机械效率,就是要找到有用功和总功。1.滑轮组机械效率决定滑轮组的机械效率的因素有以下几个:物重(负载)、动滑轮重、绳重(一般情况下忽略绳重)和绳与滑轮间的摩擦。对于同一个滑轮组承担不同物重的情形来说,动滑轮重、绳重和绳与滑轮间的摩擦近似相等,因此额外功相同,所以物重越大,有用功就越大,机械效率就越高;对于
To analyze the factors that affect the efficiency of mechanical efficiency, it is to find the factors that affect the useful work and the size of extra work. To calculate the mechanical efficiency, it is to find useful work and total work. 1. The mechanical efficiency of the pulley block The factors that determine the mechanical efficiency of the pulley block are the following: weight (load), weight pulley, rope weight (rope weight is generally ignored) and friction between the rope and the pulley. For the same pulley to assume different weights, the weight of the movable pulley, the rope weight and the friction between the rope and the pulley are approximately the same, so the extra work is the same, so the bigger the weight, the greater the useful work and the higher the mechanical efficiency ;for