英语周报外研2018－2022第九期答案

22.(1)A与B(1分)F(1分)(2)0.5(1分)0.2(2分解析:(1)当A向左运动后B处于静止状态,弹簧测力计的读数F1与B所受的滑动摩擦力F大小相等,B对木板A的压力大小等于B的重力mg,由F=F得,=p=0,为A与B之间的动摩擦因数FN mg(2)根据牛顿第二定律F-pmg=ma,得a=F=pg,所以滑块运动的加速度a和所受拉力F的关系图象斜率等于滑块和位移传感器发射部分的总质量的倒数由题图丙得加速度a和所受拉力F的关系图象斜率k=2,所以滑块和位移传感器发射部分的总质量m=0.5kg;由题图丙得在水平轨道上F=1N时,加速度a=0,根据牛顿第二定律得pmg=0,解得=0.2

阅读下列短文,从毎题所给的A、B、C、D四个选项中选出最佳选项。GloveliesUsing a phone or palmtop computer with touch screens while wearingdifficultm时hu no longer have to write teth frozen fingers.gloves with special pads(垫块) in the fingeertips to help you type or scroll ( iJ )without difficulty. They come in a range of sizes and colors. Price: $ 15.00Mini VaxIt is a tiny cleaner that you plug into(插人) your computer’ s USB port. Although it’ s smallough to fit into your pocket, the Mini Vax is very powerful and youll be amazed at how much dustd dirt it manages toip(H lK)from your computer keyboard. Your Mini Vax comes witthree attachments of different sizes to help you reach all those difficult places. Color: gray/blacPriceCheeky ClockCheeky Clock might look like a normal digital alarm clock, but the difference is that CheekyClock is a clock with wheels. When the alarm goes off in the morning, Cheeky Clock jumps downfrom your bedside table and starts running around the floor looking for a place to hide. The alarmp until you find your Cheeky Clock and switch it off. By this point, youll bIt needs three AAA batteries( not included ) Price: E40. 001. Horu properly use Clovelies?A By wearing them.B By knocking on them slightlyC. By touching the scrn themD By connecting them with your computer2. What is Mini Vax used to do?B. To improve computing speed.C. To provide power for computerD. To clean up computer keyboards3. Which of the following can best describe Cheeky Clock?A, Annoying but effective.B. Fashionable biC Fast-moving and power-savingD Clock-shaped and solar-powered

以上就是英语周报外研2018－2022第九期答案，更多英语周报答案请关注本网站。