【单选题】质量为 m 的小球在竖直平面内的圆形轨道内侧运动,经过最高点而不脱离轨道的最小速度是 v . 若小球以 2v 速度通过最高点,则它对轨道的压力为 ( )
【单选题】S1: Do you know the two basic types of cargo ships? S2: Of course. They are liquid cargo carriers and dry cargo carriers. Q: What are the two basic types of cargo ships?
A.
Container ships and oil tankers.
B.
Liquid cargo carriers and dry cargo carriers.
C.
Bulk carriers and liquid carriers.
D.
Dry cargo carriers and oil tankers.
【单选题】The types of dry cargo carriers mentioned in the passage are ________.
A.
'tween decks,OBO ships
B.
traditional dry cargo ship and multi-deck vessel
C.
OBO ships,oil tankers,chemical tankers and LNG carriers
D.
dry cargo ship,dry bulk cargo carrier,container carriers and refrigerated ships
【单选题】In dry cargo ships, the cargo space is divided into().
【单选题】质量为 m 的小球在竖直平面内的圆形轨道的内侧运动,经过最高点而不脱离轨道的临界速度为 v ,当小球以 2v 的速度经过最高点时,对轨道的压力是 ( )
【判断题】E θ (Cr 2 O 7 2- /Cr 3+ )〈E θ (Cl 2 /Cl - ),但是,K 2 Cr 2 O 7 与浓度较大的HCl(aq)可以反应生成Cl 2 。这是由于c(HCl)增大,使E(Cr 2 O 7 2- /Cr 3+ )增大,同时又使E(Cl 2 /Cl - )减小,从而使E(Cr 2 O 7 2- /Cr 3+ )〉(Cl 2 /Cl - )。
【单选题】The two basic types of cargo ships are ______.
A.
container ships and oil tankers
B.
bulk carriers and liquid carriers
C.
dry cargo carriers and oil tankers
D.
liquid cargo carriers and dry cargo carriers
【单选题】In dry cargo ships the cargo space is divided into _____, in liquid cargo ships it is divided into ______.
C.
compartments, capacity
D.
capacity, compartments
【简答题】配制1cm 3 相当于1mgFe的K 2 Cr 2 O 7 标准溶液1dm 3 ,问应称取K 2 Cr 2 O 7 样______g。
【单选题】15K 时 φ Θ Cr 2 O 7 2- /Cr 3+ =1.33V , 当 pH=1.0 , [Cr 2 O 7 2 - ]= [Cr 3+ ]= 0.1 mol·L -1 时, φ Cr 2 O 7 2 - / Cr 3 等于