Explain that light has the property of rectilinear propagation.

Dear Student,
  
Light being an electromagnetic in nature, it travels in a straight line. The phenomenon by which light travels in straight lines, unless it is reflected by a polished surface or the medium of propagation is changed.

Example :
Ray of light coming from sun

Activity:
Let us perform an activity in which we have three cardboard papers or any transparent medium of the same type and label them A, B, and C. Now put at one side of ‘A’ a source of light like candle ,open a pinhole at the middle of all the cardboard papers in a straight line making sure the light rays can be view through all, you will notice that the candle flame will be visible through the pinholes in a straight line only. This shows light is propagated rectilinearly.  



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