Archive for the ‘Light and Sound’ Category

Image from hyperphysics.phy-astr.gsu.edu

At supersonic speeds (those greater than the local sound speed), there is no sound heard as an object approaches an observer because the object is traveling faster than the sound it produces. Only after the object has passed will the observer be able to hear the sound waves emitted from the object. These time periods are often referred to as the zone of silence and the zone of action. When the object has passed over the observer, the pressure disturbance waves (Mach waves) radiate toward the ground, causing a sonic boom. The region in which someone can hear the boom is called the boom carpet. The intensity of the boom is greatest directly below the flight path and decreases on either side of it.

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Image from aviation.stackexchange.com

And one video: Breaking the sound barrier [Jets Compilation]





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(Natural Sciences: PHYSICS) 2º ESO

  1.  Read the problem carefully
  2.  Write the formula that you need.
  3.  Use the data that you know.
  4.  Calculate.
  5.  Write the result with the correct units.


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This was the fantastic project done by David Aladrén and Pablo Torralba, students from 2ESO D.

In this presentation they explain step by step the whole process to make the kaleidoscope:


It is one example of the Light expriments done by the kids during Xmas holidays.

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In this presentation you  can find a compilation of simple light experiments extracted from the book Simple Science Experiments (HANS JURGEN PRESS). These experiments and science crafts are very suitable for 2º ESO Natural Science.

The work will be evaluated according to its Experiment

  • Difficulty and originality

Then you will have to present your work to the group, in you Presentation it will be evaluated the following:

  • Speak in a clear and fluent manner.
  • Connect with the audience
  • Accurate vocabulary
  • Scientific concepts.

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