利用等值单摆长，考虑漏摆尺寸对周期的影响，推导了圆台形漏摆的周期随流体下落高度变化的规律.发现当液面下降时，漏摆的周期先增大，达到极大值后再减小; 漏摆内流体密度越大，周期最大值越大.推导方法可以推广至其它旋转体，比如圆锥体、圆柱体等.利用级数法分析表明漏摆的周期变化主要由其自身性质( 摆长、摆锤尺寸等) 决定，当摆长远大于摆锤自身尺寸时，漏摆质量变化的影响可以忽略，可以用作单摆等周期运动的演示.最后实验验证了圆台形漏摆周期随高度的变化规律，与理论推导结果一致.

With the equivalent length of pendulum，considering the effect of pendulum size on its period，the variation of period for leaky circular truncated cone pendulum with the height of liquid in it is deduced. Consequently， with the height of liquid descending，the period of the leaky pendulum increases first，reaches its maximum and then decreases. Specifically，the greater the density of the fluid is，the greater the maximum is. The above conclusion can be used to other rotating bodies，such as cone and cylinder，etc. After that，using the series method，it is found that the period of leaky pendulum is mainly determined by its nature，that is，pendulum length and pendulum size. It means that the pendulum length is far larger than the pendulum bob，the variation of its mass can be ignored， which can be used to demonstrate the motion of simple pendulum. Finally，the period of leaky circular truncated cone pendulum varying with the liquid height has been measured experimentally，which is in good agreement with the present theoretical conclusion.