题目

如图所示,一质量为m的小球,用长为L的轻绳悬挂于O点,初始时刻小球静止于P点。第一次小球在水平拉力F1作用下,从P点缓慢地移动到Q点,此时轻绳与竖直方向夹角为θ=60°,张力大小为T1;第二次在水平恒力F2作用下,从P点开始运动并恰好能到达Q点,至Q点时轻绳中的张力大小为T2,不计空气阻力,重力加速度为g,关于这两个过程,下列说法中正确的是( )A.,B.两个过程中F1和F2做的功相同C.两个过程中,轻绳的张力均变大D.第一个过程中,拉力F1在A)根据句意,用括号中所给单词的正确形式填空,每空一词。【1】President Xi spoke ________(高度地)of WangJicai, who devoted himself to guarding Kaishan Island.【2】New drivers usually have difficulty _______(停车)their cars in a designated area.【3】Adelaide, an Australian coast city _______(记录) the hottest dayin history with a temperature of 46.6℃ on January 24,2019.【4】Who is ________(愚蠢), the emperor or the young boy in the story The Emperor’s New Clothes?【5】Do you know how many_______(排)there are in Wanda Cinema?
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