Question

一列簡(jiǎn)諧橫波沿x軸傳播,頻率為5 Hz,某時(shí)刻的波形如圖所示.介質(zhì)中質(zhì)點(diǎn)A的平衡位置在距原點(diǎn)8  cm處,質(zhì)點(diǎn)B在距原點(diǎn)16  cm處,從圖象對(duì)應(yīng)時(shí)刻開始計(jì)時(shí),質(zhì)點(diǎn)B的運(yùn)動(dòng)狀態(tài)與圖示時(shí)刻質(zhì)點(diǎn)A的運(yùn)動(dòng)狀態(tài)相同所需的最短時(shí)間可能是(    )

A．0.08 s	B．0.12 s
C．0.14 s	D．0.16 s

Answer 1

AB

考查波的圖象及其對(duì)圖象的理解和應(yīng)用.由題意可知,周期T=="0.2" s,由圖象可知該波的波長(zhǎng)λ="0.2" m,所以波速v=="1" m/s.當(dāng)波沿x軸負(fù)方向傳播時(shí),最短距離sBA="0.08" m,所以最短時(shí)間t1=="0.08" s,A對(duì);當(dāng)波沿x軸正方向傳播時(shí),最短距離sBA="0.12" m,所以最短時(shí)間t2=="0.12" s,B對(duì);C?D均錯(cuò).