题目

如图所示，M、N为两个固定的等量同种正电荷，在其连线的中垂线上的P点（离O点很近）由静止开始释放一电荷量为-q的点电荷，不计重力，下列说法中正确的是（） A . 点电荷在从P到O的过程中，加速度越来越大，速度也越来越大 B . 点电荷在从P到O的过程中，加速度越来越小，速度也越来越小 C . 点电荷运动到O点时加速度为零，速度达最大值 D . 点电荷越过O点后，速度越来越小，加速度越来越大，直到粒子速度为零阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。On Tuesday evening, Zhong Nanshan, a【1】(lead) respiratory disease expert, was invited to participate in an online live broadcast hosted by Tencent to share his 【2】(late) views on COVID-19.Chinese medicine【3】(have) some certain effects on the【4】(prevent) and control of COVID-19. For example, Lianhua Qingwen medicine might be a little weaker; against novel coronavirus pneumonia, but it has a good inhibitory effect on damage【5】tissue cell inflammation 【6】 (cause) by the epidemic. And it's proved effective to reduce fever, cough, and speed up【7】(recover). 【8】(consist) of five herbal extracts, Xuebijing, an injection developed and marketed during the severe acute respiratory syndrome (SARS) epidemic in 2003, can relieve symptoms and reduce the rate of fatalities. We can’t judge 【9】 the Chinese medicine or western medicine treatment is effective just based on impressions, 【10】we can prove it according to medical methods.