题目

A black hole is a place in space where gravity pulls so much that even light cannot get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying. Because no light can get out, people can’t see black holes. Space telescopes with special tools can help find black holes. The special tools can see how stars that are very close to black holes act differently from other ones. Black holes can be big or small. Scientists think the smallest black holes are as small as just one atom. These black holes are very tiny but have the mass一列沿x轴正方向传播的简谐横波在x1=0.1m和x2=1.1m处的两质点的振动图线,如图所示.则这列简谐波的周期和波长各为多少?
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