The world renowned British Physicist Stephen Hawking who tried to explain the mysteries of the universe to millions of people passed away on March 14th, 2018 at the age of 76. His family said he died peacefully at his home in Cambridge. Professor Hawking used wheelchair and was able to speak only through a computer synthesizer(合成器), having been suffering from a rare form of motor neuron disease as a young man. Despite being given only a few years to live, he wrote popular science books for several decades. A film about his life The Theory of Everything won an Oscar for the actor Eddie Redmayne who portrayed him.

    Stephen's daughter Lucy spoke about her father's love of the limelight in 2012. She said, “Actually my father is also a showman. He loves a big show, a big stage and bright light, whether it's him on stage or whether it's watching the spectacle.”

    Stephen Hawking's death was announced in the statement by his children who said they will miss him forever. They said his courage and brilliance inspired people across the world. Many leaders from different countries paid tribute(致敬) to him including the Indian Prime Minister Narendra Modi, who said Professor Hawking had made the world a better place.

在2012年昌平第七届国际草莓节上，人们利用悬挂式栽培法营造出了别具一格的草莓景观（见下图）。据此完成小题。

如图所示，两物块A、B套在水平粗糙的CD杆上，并用不可伸长的轻绳连接，整个装置能绕过CD中点的轴OO₁转动，已知两物块质量相等，杆CD对物块A、B的最大静摩擦力大小相等，开始时绳子处于自然长度（绳子恰好伸直但无弹力），物块B到OO₁轴的距离为物块A到OO₁轴的距离的两倍，现让该装置从静止开始转动，使转速逐渐慢慢增大，在从绳子处于自然长度到两物块A、B即将滑动的过程中，下列说法正确的是（   ）