【正文】 位置處兩球的總動能為 。 一物體由靜止開始從軌道頂端滑下，當(dāng)其到達(dá)軌道底部時(shí)，物體的速率為 ，其水平方向的速度 大小為 。 (1)當(dāng)小車勻加速經(jīng)過光電門時(shí)，測得兩擋光片先后經(jīng)過的時(shí)間 1t? 和 2t? ，則小車加速度 a? 。 (1)(多選題 )在實(shí)驗(yàn)中需保持不變的是 ( ) (A)擋光片 的寬度 (B)小車的釋放位置 (C)導(dǎo)軌傾斜的角度 (D)光電門的位置 7 (2)線圈匝數(shù)增加一倍后重做該實(shí)驗(yàn)，在圖 (b)中畫出實(shí)驗(yàn)圖線 。 (1)定值電阻應(yīng)選 ，滑動變阻器應(yīng)選 。 六．計(jì)算題 (共 50分 ) 8 30.(10 分 )如圖，絕熱氣缸 A與導(dǎo)熱氣缸 B均固定于地面，由剛性 桿連接的絕熱活塞與兩氣缸間均無摩擦。 31． (12 分 )如圖，質(zhì)量 2m kg? 的物體靜止于水平地面的 A處， A、 B間距 L=20m。 的力斜向上拉此物體，使物體從 A處由靜止開始運(yùn)動并能到達(dá) B處，求該力作用的最短時(shí)間 t。 (取 210 /g m s? )求： (1)金屬棒在此過程中克服安培力的功 W安 ； (2)金屬棒下滑速度 2/v m s? 時(shí)的加速度a ． (3)為求金屬棒下滑的最大速度 mv ，有同學(xué)解答如下：由動能定理 21=2 mW W mv重 安， ??。將 B在 A附近某一位置由靜止釋放，由于能量守恒，可 通過測量 B在不同位置處的速度，得到 B的勢能隨位置 x的變化規(guī)律，見圖 (c)中 曲線 I。 (4)若 A、 B異名磁極相對放置，導(dǎo)軌的傾角不變，在圖 (c)上畫出 B的總勢能隨 x的變化曲線． 11 20xx年全國普通高等學(xué)校招生統(tǒng)一考試 上海物理試卷答案要點(diǎn) 第 I 卷 (共 56 分 ) 一．單項(xiàng)選擇題 (共 16 分，每小題 2 分 。 ) ，波動說 ，不守恒 22B．增大，增大 23. 12( ) / 2q q El? ， 1 2 2 1[ ( ) ( ) ] / 2q q E m m g l? ? ? ， 0 25. 0/gs v ， 2200/ 1 ( / )v v gs? 五 .實(shí)驗(yàn)題 (共 24 分 ) 26． （ 1） 2222111[]2 ( ) ( )bd t t??? (2)B， C (3 分 ) 27.(1) ② 在量筒中滴入 N滴溶液 (1 分 ) ③ 在水面上先撒上痱子粉 (1 分 ) (2) 10?? (3 分 ) 28． (1) A， D (3 分 ) (2)見圖 (2 分 ) 29. 12 (1)③ ， ⑥ (各 1 分 ) (2)見圖 (2 分 ) (3)① 將滑動觸頭移至最左端 ( 寫最小給分，最大不給分 ) (1 分 ) ③ 多次移動滑動觸頭，記錄相應(yīng)的 1G ， 2G 讀數(shù) 12,II (1 分 ) (4) 11( 1)r k R?? (3 分 ) 六．計(jì)算題 (共 50 分 ) 30.(10 分 ) 設(shè)初態(tài)壓強(qiáng)為 0p ， 膨脹后 A， B 壓強(qiáng)相等 ? (1 分 ) B 中氣體始末狀態(tài)溫度相等 0 0 0 ( 2 )Ap V p V V?? (3 分 ) ∴076AVV? (1 分 ) A 部分氣體滿足 0 0 0 00Ap V p VTT? （ 4 分） ∴ ? （ 1 分） 31． (12 分 ) (1)物體做勻加速運(yùn)動 2012L at? (1 分 ) ∴ 22202 2 2 0 1 0 ( / )2La m st ?? ? ? （ 1 分） 由牛頓第二定律 F f ma?? （ 1 分 ） 30 2 10 10 ( )fN? ? ? ? (1 分 ) ∴ 10 0 .52 1 0fmg? ? ? ?? (1 分 ) (2)設(shè) F 作用的最短時(shí)間為 t ，小車先以大小為 a 的加速度勻加速 t 秒，撤去外力后，以大小為 39。39。39。無論最終是否達(dá)到勻速，當(dāng)棒到達(dá)斜面底端時(shí)速度一定為最大。 （ 2 分） .c 16 20xx年普通高等學(xué)校招生全國統(tǒng)一考試 （北京卷） 英 語 本試卷共 16 頁，共 150 分。 第一部分：聽力理解 （共三節(jié)， 30 分） 第一節(jié)（共 5 小題：每小題 分，共 分） 聽下面 5 段對話。 例： What is the man going to read? A． A newspaper. B． A magazine. C． A book. 答案是 A。聽完后，每小題將給出 5 秒鐘的作答時(shí)間。 8． What does the man think is the cause of the woman‘s illness? A． Last night‘s dinner. B． The hot weather. C． Bottled water. 9． What is the probable relationship between the two speakers? A． Husband and wife. B． Doctor and patient. C ． Guest and receptionist. 聽第 8 段材料，回答第 10 至 12 題。 Missing Person Report Form Time last seen About 16 o‘clock in the afternoon Place last seen At the 17 section of the store Name 18 Age Five Appearance Dark 19 hair, thin and small Clothing Blue 20 , a pink Tshirt, a hat 第二部分：知識運(yùn)用（共兩節(jié)， 45 分） 第一節(jié) 單項(xiàng)填空（共 15 小題；每小題 1 分，共 15 分） 從每題所給的 A、 B、 C、 D 四個(gè)選項(xiàng)中，選出可以填入空白處的最佳選項(xiàng)，并在答題卡上將該項(xiàng)涂黑。 A “I Went Skydiving at 84!” As a young girl growing up in the 1930s, I always wanted to fly a plane, but back then it was almost unheard of a woman to do that. I got a taste of that dream in 20xx,when my husband arranged for me to ride in a hot air balloon for my birthday. But the experience turned out to be very dull. Around that time ,I told my husband that I wanted to skydive. So when our retirement munity（社區(qū)） announced that they were having an essay petition and the topic was an experience of a lifetime that you wanted to have, I decided to write about my dream. In the essay, I wrote about my desire to skydive, stating Gee Brush Sr. did it at age 80. Why not me? I was just 84 and in pretty good health. A year went by and I heard nothing. But then at a munity party in late April 20xx, they announced that I was one of the winners. I just couldn‘t believe it. Inspired by this, I decided to realize my dream, even though some of my 22 family members and my doctor were against it. One June 11, 20xx, nearly 40 of my family and friends gathered in the area close to where I would land while I headed up in the airplane. My instructor, Jay, guided me through the experience. The plane was the noisiest one I had ever been in, but I wasn‘t frightened—I was really just looking forward to the experience. When we reached 13,000 feet, Jay instructed me to throw myself out of the plane. When we first hit the air, the wind was so strong that I could hardly breathe. For a second I thought, ―What have I gotten myself into?‖ But then everything got calmer. We were in a free fall for about a minute before Jay opened the parachute（降落傘） , then we just floated downward for about five minutes. Being up in the clouds and looking at the view below was unlike anything I have ever felt—much better than the hot air balloon. I was just enjoying it. Skydiving was really one of the greatest experiences of my life. I hope other people will look at me and realize that you don‘t stop living just because you are 84 years old. If there‘s something you want to experience, look into it. If it‘s something that is possible, make it happen. 56． What happened to the author in 20xx? A． She flew an airplane B． She entered a petition C． She went on a hot air balloon ride D． She moved into a retirement munity 57． The author mentioned Gee Bush Sr. in her essay to