【单选题】下列各溶液中,Na + 浓度最大的是( )
D.
0.2L0.15mol/L的Na 3 PO 4
【单选题】下列溶液中Cl - 浓度最大的是( )
C.
0.1L0.1mol?L -1 的AlCl 3 溶液
D.
0.3L0.1mol?L -1 的MgCl 2 溶液
【单选题】As shown in the figure, the lengths of the cantilever beam and the simply supported beam are the same. For the Fs diagrams and M diagrams of the two beams, which of the following statements is true?
A.
Both Fs and M diagrams of the two beams are the same.
B.
Both Fs and M diagrams of the two beams are different.
C.
Fs diagrams of the two are the same, M diagrams are different.
D.
Fs diagrams of the two are different, M diagrams are the same.
【单选题】In a Young’s experiment, it is essential that the two beams
A.
have exactly equal intensity
C.
travel equal distances
D.
come originally from the same source
【单选题】Knowing that both the bending stiffness EI and the exerted loads of the two beams in the shown figures are the same. Which of the following statements is correct?
A.
The internal forces and displacements of the corresponding points of the two beams are the same.
B.
The internal forces and displacements of the corresponding points of the two beams are different.
C.
The internal forces of the corresponding points of the two beams are the same, while displacements are different.
D.
The internal forces of the corresponding points of the two beams are different, while displacements are the same.
【单选题】You ______ your own sandwiches. I have enough for two.
C.
shouldn' t have brought
【单选题】You ______ your own sandwiches. I have enough for two.
B.
shouldn't have brought
【单选题】The material and cross-section of the two beams are the same (as shown in the figure), then the ratio of the maximum deflection of the two beams ( y a : y b ) is .