求解~🙏🫡

Example 5 大利坐在蘋果樹下思考物理,突然一顆質量200克的蘋果從3.2公尺的高處自由落下,不偏不倚 打中大利頭頂,而且正向反彈高度為5公分(蘋果與頭接觸時間0.1秒)。 試問在蘋果與頭接觸的過程中,蘋果平均所受淨力為多少牛顿?(令g=10公尺/秒2) (A)20 (B)18 (C)16 (D)14 。 【中正、中山女、南一中】(B)

可是他沒有給磚塊的密度欸

Example 1 質量應用 1.古夫金字塔是用大約230萬塊巨石建成的,塔尖高度約為146公尺,塔底寬度約為230公尺, 故其體積約為257萬立方公尺,利用以上數據來估計,此金字塔每塊巨石的平均質量,與下 列何者最為接近? (A) 500 (B)1000 (C)2500 (D)6000 (E)9000 公斤。 【學測、板中】(C) 2. 在熔製玻璃的過程中

請問例題7怎麼算

《Example 7》- 邊長a之均勻立方體木塊,比重為p,浮在比重為d之液體中(d>p),問: (a)欲使木塊全部沒入液中,至少需作功若干? (b)若木塊恰完全沒入液面時,再使其深入,至少需作功若干?

第七題的A和B（A對B錯

自然考科 Professional ACDE 6. 邊長為d之正三角板 ABC 各頂點分別有質點m=m&mp=2m, me=3m,此系統之質心距議議 √13d 之距離為何? √19d √id (A). (B) (C) Vid (D). (E) 6 6 6 5 4 【北模】。 【解說】 (0,0):A(d,0):C( 興 x=" 【解說】(A) mxd+3mx0.5d 5d 6m 12 L 3mod fod √x + √ √√3d √13d 6m 4 6 Th √√31 Ta X %= L 一均勻密度的矩形薄木板,厚度各處相同,長度為x,寬度為2L,重 量為 W,以兩繩A及B垂直懸掛在天花板上,如右圖所示。兩繩A及B 的長度分別為 L 及 2L,則當木板處於靜止狀態時,下列敘述何者正確? (A)當x=L時,則繩4的張力較繩 B 的張力大 (B)不論x 值為何,繩 4 的張力恆等於繩 B 的張力 (C)不論x 值為何,繩 4 的張力恆大於繩 B 的張力 (D) 當x≥ 23 L 時,繩B的張力為零 (E)不論x 值為何,繩A的張力與繩 B 的張力對木板重心之力矩,量值恆相等。 (B) B x=0 T -30°.. G A (C) 30% V. 2L >L Tºcos30T-00530) 六月 由 La、Lo得知 )=i TB>TA ..x=0=T₁=TB (A)由於力矩相等,故T>T; (B)只有當 X極小時 Tx=TB (D)當 X=25L 時,木塊質心恰好在 A 正下方,故TA = Wg,Tg=0且X>23L a x=2√3L Example 2. 如圖,A、B二物體的質量均為m, (1)滑輪受桌子之支撐力大平 (2)系統然掌沙力量值為 (3)系統寶心加速度大小為 【解說】 【北模】(A)(C)(DWE mg-T = ma 1T=ma T= mªda 2 B繩會軟掉,T 始終為0 類題→人生有兩齣悲劇 1. 有兩個體積相同 於光滑水平面上 量J,其俯視圖 動情形,下列 Emqu E 2 2m 8.光滑水平地面上靜置一長板,板上有一人相對於板面自靜止開始向右直行,如圖所示。若長板和 因地面光滑而可完全忽略,則下列相關敘述何者 (剛體受力運重 (A)兩球系統 (B)兩球系結 (C)兩球系 (D)兩球系 (E)兩球有 【解說】依據

這題為何是B

Which pair of vectors is not always in parallel? (A) Velocity & linear momentum; (B) Angular velocity & angular momentum; (C) Net force & acceleration; (D) All; (E) None.

為什麼有2？

Example 4:一無限寬的電荷片上有均匀的面電荷 密度o C/m2。求其電場。 E(r) = E("\r O A -> Q=2 A E Eo .. E= E-0如果它的方向是離開電荷。 2 Eo

21題 教教我QAQ

Section 11.3 Angular Momentum J-s behind rmv a he ur 265 = ? a ter 30. Example 11.1: A 58.1 Iw COMP string and whirled at 18. Express the units of angular momentum (a) using only the funda- momentum of magr mental units kilogram, meter, and second; (b) in a form involving the circular path. Fir newtons; (c) in a form involving joules. marw horizontal and (b) the 19. Use data from Appendix E to make an order-of-magnitude esti- 31. Example 11.2. A stai mate for the angular momentum of our Solar System about the Max 27 the end of its lifetime galactic center. mu = 17.293 of radius 4.96 X 10' 20. A gymnast of rotational inertia 63 kg•m? is tumbling head over heels dwarf of radius 4.21 with angular momentum 460 kg•m?/s. What's her angular speed? 17.99 acted on the core, fine A 660-g hoop 95 cm in diameter is rotating at 170 rpm about its 32. Example 11.2: Astro 22. A 1.3-th-diameter golf ball has mass 45 g and is spinning at central axis. What's its angular momentum? L: 1W=0-66*(0-95) x 140x277.10 km and determin core that collapsed to 3000 rpm. Treating the golf ball as a uniform solid sphere, what's ing with a period of 4 its angular momentum? 18-3 33. Example 11.2. The s 10-598 rpm With her arms outstre Section 11.4 Conservation of Angular Momentum tational inertia is 3.5 23. A potter's wheel with rotational inertia 6.20 kg•m? is spinning (Fig. 11.6b), her rot freely at 20.0 rpm. The potter drops a 2.50-kg lump of clay onto her final spin rate? L = 6 2 x 2-1 = 12-99~13 - 2x2 22 13= 60.48)" x 2.5 W W = 2 . X z W = 20x2T 60 ²2.1 ~ 1 12.574

第21題 到底要怎麼寫ಥ_ಥ

Section 11.3 Angular Momentum J-s behind rmv a he ur 265 = ? a ter 30. Example 11.1: A 58.1 Iw COMP string and whirled at 18. Express the units of angular momentum (a) using only the funda- momentum of magr mental units kilogram, meter, and second; (b) in a form involving the circular path. Fir newtons; (c) in a form involving joules. marw horizontal and (b) the 19. Use data from Appendix E to make an order-of-magnitude esti- 31. Example 11.2. A stai mate for the angular momentum of our Solar System about the Max 27 the end of its lifetime galactic center. mu = 17.293 of radius 4.96 X 10' 20. A gymnast of rotational inertia 63 kg•m? is tumbling head over heels dwarf of radius 4.21 with angular momentum 460 kg•m?/s. What's her angular speed? 17.99 acted on the core, fine A 660-g hoop 95 cm in diameter is rotating at 170 rpm about its 32. Example 11.2: Astro 22. A 1.3-th-diameter golf ball has mass 45 g and is spinning at central axis. What's its angular momentum? L: 1W=0-66*(0-95) x 140x277.10 km and determin core that collapsed to 3000 rpm. Treating the golf ball as a uniform solid sphere, what's ing with a period of 4 its angular momentum? 18-3 33. Example 11.2. The s 10-598 rpm With her arms outstre Section 11.4 Conservation of Angular Momentum tational inertia is 3.5 23. A potter's wheel with rotational inertia 6.20 kg•m? is spinning (Fig. 11.6b), her rot freely at 20.0 rpm. The potter drops a 2.50-kg lump of clay onto her final spin rate? L = 6 2 x 2-1 = 12-99~13 - 2x2 22 13= 60.48)" x 2.5 W W = 2 . X z W = 20x2T 60 ²2.1 ~ 1 12.574

請問這題，時間怎麼算？ 答案是1.7秒 但我一直算出1.24秒

EXAMPLE 2.6 Constant Acceleration Due to Grav You toss a ball straight up at 7.3 m/s; it leaves your hand at 1.5 m above the floor. Find when it hits the floor, the maximum height it reaches, and its speed when it passes your hand on the way down.

第二題，求過程，謝謝，答案是6a

1-2 電場與電力線 EXAMPLE 範列1-4 142 10 -X 如圖所示,將點電荷 +42 固定於平面坐標之原點O,另 一點重荷-2 固定於C點(坐標x=3a),則: - (1) 4 處賣場為何? 公式型(靜態平衡狀態) 平贸。 *20 / +9 x=ya (2) 軸上,何處電場為零? x-a 团靜態推動態 觀念分析 1. 天預現) (EliQ test cha 空間中某處的電場,為各個場源電荷在該處所建立電場的向量和。 charge