近几年 ,在各级各类的考试题中 ,一类“可能”型的电学单选题 (题干最后一般都有“可能是”几个字 )时常出现 .这类题由于其中的一定值电阻在题目所涉及的两种电路状态下均出现 ,但具体阻值不知道 ,而利用题目所给的已知量又无法直接求得所求量的具体值 ,于是许多同学面对这类 In recent years, among the various types of examination questions, one type of “possible” type of electric single choice question (the end of the question usually has “may be” words) often appears. Such questions are due to certain Value resistors appear under the two circuit conditions involved in the problem, but the specific resistance value is not known, and the known value given by the use of the problem cannot directly obtain the specific value of the requested quantity. Therefore, many students face this type of resistance.