A particle is in simple harmonic motion with period T. At time t = 0 it is at the equilibrium point. Of the following times, at which time is it furthest from the equilibrium point?
A. 0.5T
B. 0.7T
C. T
D. 1.4T
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A subatomic particle when at rest typically exists for about 20 ns before it decays. A beam of such particles is created traveling at 0.60c with respect to the laboratory. How far might such a particle travel in the lab before it decayed?
A. 4.5m
B. 9m
C. 12m
D. 15m
在部分响应系统中,采用预编码和相关编码目的之一是
A. 无码间干扰
B. 引入受控的码间干扰
C. 减少抽判时的电平数目
D. 避免差错传播现象
某离散信源发送M进制消息,其平均信息量最大时的概率分布为
A. 均匀分布
B. 正态分布
C. 瑞利分布
D. 指数分布
在等概的情况,以下数字调制信号的功率谱中不含有离散谱的是
A. OOK
B. MASK
C. 2FSK
D. 2PSK