题目

Silence is unnatural to man．He begins life with a cry and ends it in stillness．In between he does all he can to make a noise in the world, and he fears silence more than anything else．Even his conversation is an attempt to prevent a fearful silence．If he is introduced to another person, and a number of pauses occur in the conversation, he regards himself as a failure, a worthless person, and is full of envy of the emptiest headed chatterbox （喋喋不休的人）．He knows that ninety-nine percent of human conversation means no more than the buzzing of a fly, but he is anxious to jo 如图所示，小球的质量为m，L2为质量不计的轻弹簧，一端悬挂在天花板上，与竖直方向夹角为，L1为一水平轻绳，若将L2剪断瞬间小球的加速度为________，若将L1剪断瞬间小球的加速度为________．