Ls 發問於 科學及數學物理學 · 4 年前

Please help. One MC about wave and one about lens?

For Q15. Does it mean when one wave particle is at rest, all other particle must be at rest? When one is moving all other particles are moving? (except the nodes)

For Q16, why can't a convex lens with object distance 5.5cm be used? the image is magnified and the object distance is smaller than the focal length.

Thanks for your help

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1 個解答

  • 天同
    Lv 7
    4 年前

    15. Yes.

    All particles in a stationary wave are moving in phase. If not, then the "crest" (the anti-node) would be moving forward and it is not a stationary wave.

    16. I could only say that if you choose option C, the focal length of the convex lens works out to be 12.2 cm, and which is not exactly 12 cm as given in the question.