• earnest erihbra the power of focus
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    why is it that light rays converged on a polythene by a converging lens always get the stuff melted......nedd detailed xplanations     24 October 2010Comment
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    • ogugua belonwu The sun emits a particle known as a photon, which carries visible light to earth. These photons contain energy, which they radiate in the form of heat.

      Normally, the photons wont cause any probs in their normal state.

      When you put a magnifying glass or a convex lens in the paths of these photons, the convex lens narrows and focuses the photons, making them converge on a narrower point than if the lens wasn't there.

      This concentration of photons concentrates the heat that they emit, heating the polythene up until it ignites at a certain temperature.
      Like It0 Unlike It0 24 October 2010
    • earnest erihbra what if the polythene is replaced by an exposed skin...will it cause the same heating and melting effect
      Like It0 Unlike It0 25 October 2010
    • ogugua belonwu yeah it will cause the same heating effect, might lead to slight burns if exposed over a long period of time
      Like It0 Unlike It0 25 October 2010
    • martin ozioko hydration takes effect before burnt.
      Like It0 Unlike It0 20 March 2011
    • ogugua belonwu hydration?? i think hydration is adding water, pls explain
      Like It0 Unlike It0 20 March 2011
    • nicholas bertrand anakwue Well, the converging lens, converges rays that hit it. So when placed at a position btw the principal focus and the pole of the lens, it magnifies the suns heat rays and concentrates it on the surface of the polythene. If u were with a diverging lens, the effect wont be the same, cuz the rays are diverted and not concentrated on the spot of the paper.
      Like It0 Unlike It0 16 May 2011