【单选题】For two particles with masses of 【图片】and 【图片】,their speeds at some instant are 【图片】and 【图片】,respectively. Which statement is correct?
A.
If and , the momenta of these two particles must be the same.
B.
If and , the momenta of these two particles can also be the same.
C.
If and , the momenta of these two particles can also be the same.
D.
If and , the momenta of these two particles must be different.
【单选题】If two particles have equal momenta, are their kinetic energies equal?
C.
no, except when their speeds are the same
D.
yes, as long as they move along parallel lines
【单选题】表达式“abc,"+"123"的值为( )。
【单选题】林某,男,35岁,肝硬化腹水,近日神志恍惚、躁动不安、答非所问,此情况属于
【单选题】负债的按周转时间的长短 划分,可分为长期负债和( )
【单选题】A2型题 8.林某,男35岁,肝硬化腹水,近日神志恍惚、躁动不安、答非所问,此情况属( )。
【单选题】Which two particles would be attracted to each other?
A.
electrons and neutrons
D.
all particles are attracted to each other
【单选题】听力原文:M: The teacher called off the lecture. W: Oh, really? His student John must be disappointed at this news. Q: Who is John ? (5)
【单选题】John is a good student, ______ his best subject.