试题与答案

如图所示,在高为L的木箱abcd的底部放有一个小物体Q(可视为质点),现用力F向

题型:选择题

题目:

如图所示,在高为L的木箱abcd的底部放有一个小物体Q(可视为质点),现用力F向上拉绳,使木箱由静止开始运动,若保持拉力的功率不变,经过t时间,木箱达到最大速度,这时让木箱突然停止,小物体由于具有惯性会继续向上运动,且恰能达到木箱顶端.若重力加速度为g,空气阻力不计,以下说法正确的是(  )

A.木箱即将达到最大速度之前,物体Q处于失重状态

B.木箱突然停止运动时,物体Q处于超重状态

C.木箱的最大速度为

2gL

D.由于木箱和小物块的质量未知,故无法确定t时间内木箱上升的高度

答案:

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题型:问答题

根据信用证和补充资料指出海运提单和商业发票中错误的地方。
(1)信用证
Form of Doc. Credit *40A: IRREVOCABLE
Doc. Credit Number *20: LC-320-0254771
Date of Issue *31C: 090922
Expiry *31D: Date 061222 Place CHINA
Applicant *50: MARCONO CORPORATION
RM1001, STAR BLDG. TOKYO. JAPAN
Beneficiary *59: QINGDAO(SHANDONG)HUARUI CO.
NO. 35 WUYI ROAD QINGDAO,
CHINA
Amount *32B: Currency USD Amount 70000.00
Pos./Neg. Tol.(%)*39A: 5/5
Available with/by *41D: ANY BANK
BY NEGOTIATION
Draft at42C: DR AFIS AT SIGHT FOR FULL INVOICEVALUE
Drawee 42A: ROYAL BANK LTD, TOKYO
Pattial Shipments 43P: ALLOWED
Transshipment 43T: NOT ALLOWED
Loading in Charge 44A: SHIPMENT FROM CHINESE MAIN PORT
For Transport to44B: OSAKA, JAPAN
Latest Date of Ship. 44C: 061210
Descript. of Goods 45A:
HALF DRIED PRUNE 2005 CROP
GRADE SPEC QNTYUNIT PRICE
(CASE) (USD/CASE)
A L: 500CASE M: 500CASE 1,000 22.0 CFR OSAKA
B L: 1200CASE M: 1200CASE 2,400 22.0 CFR OSAKA
PACKING: IN WOODEN CASE, 12KGS PER CASE
TRADE TERMS: CFR OSAKA
Documents required 46A:
+FULL SET OF CLEAN ON BOARD OCRAN BILLS OF LADING MADE OUT
TO ORDER OF SHIPPER AND BLANK ENDORSED AND MARKED
"FREIGHT PREPAID" AND "NOTIFY MARCONO CORPORATION. RM1001。
STAR BLDG. TOKYO, JAPAN"
+MANUALLY SIGNED COMMERCIAL INVOICE IN TRIPLICATE(3)INDI-
CATING APPLICANT’S REF. NO.SCLI-98-0474.
+PACKING LIST IN TRIPLICATE(3).
Details of Charges 71B: ALL BANKING CHARGES OUTSIDE JAPAN
ARE FOR ACCOUNT OF BENEFICIARY
Presentation Period 48: DOCUMENTS TO BE PRESENTED WITHIN
15 DAYS AFTER THE DATE OF SHIP-
MENT. BUT WITHIN THE VALIDITY OF
THE CREDIT.
(2)补充资料
发票号码:76IN-C001, 发票日期:2009年9月8日
提单号码:NSD220055, 提单日期:2009年12月5日
船名:FENGLEIV. 66026H装运港:青岛港
集装箱:2×20’ FCL CY/CY 出口口岸:青岛海关
TRIU 1764332 SEAL05003合同号:HA1101
KHLU1766888 SEAL05004SHIPPING MARKS(唛头):
出口商;青岛华瑞贸易公司 MQ
净重:12.00KGS/CASE HA1101
毛重:14.00KGS/CASE OSAKA
尺码:(20×10×10)CM/CASE NO.S1-3400
(3)海运提单


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