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CBSE Class 9 Answered

frequency of infrasound & ultrasound
Asked by indrayani | 22 Jan, 2010, 05:07: PM
answered-by-expert Expert Answer

Dear Student

We cant hear  infrasound &ultrasound, similarly we can not here , see, sense somany phyical relities like nuclear dadiation, X rays ,gamma rays etc.    Based on observable effect by these things onacn deduce its presence.

One can indirectly see/observe  the waves through acientific instruments.

Regards

Team

Topperlearning

Answered by | 22 Jan, 2010, 08:10: PM

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