对物理量的数量级大致估算的题目称为估算题．比之常规的计算题，它虽不是精确严密地求解，但其推算是合理的近似，可以避免陷入数学繁琐演算的困境，找到简明的思考方法．更有利于培养同学们思维的敏捷性和解决实际问题的能力． 物理估算题，在新编中学物理教材中占有一定的数 The approximate magnitude of the physical quantity is called the estimation of the title. Compared with the conventional calculation problem, although it is not accurately and strictly solved, its calculation is a reasonable approximation, which can avoid falling into the dilemma of math complicated calculation and find a concise way of thinking. More conducive to cultivate the students the agility of thinking and the ability to solve practical problems. Physics estimation problem, in the new middle school physics textbooks occupy a certain number