一谐振子作振幅为A的谐振动，它的动能与势能相等时，它的相位和坐标分别为：A. pm (pi)/(3), pm (2)/(3)pi; pm (sqrt(3))/(2)AB. pm (pi)/(4), or pm (3)/(4)pi; pm (sqrt(2))/(2)AC. pm (pi)/(6), pm (5)/(6)pi; pm (sqrt(3))/(2)AD. pm (pi)/(3), or pm (2)/(3)pi; pm (1)/(2)A

A. $\pm \frac{\pi}{3}$, $\pm \frac{2}{3}\pi$; $\pm \frac{\sqrt{3}}{2}A$

B. $\pm \frac{\pi}{4}$, or $\pm \frac{3}{4}\pi$; $\pm \frac{\sqrt{2}}{2}A$

C. $\pm \frac{\pi}{6}$, $\pm \frac{5}{6}\pi$; $\pm \frac{\sqrt{3}}{2}A$

D. $\pm \frac{\pi}{3}$, or $\pm \frac{2}{3}\pi$; $\pm \frac{1}{2}A$