Laws Of Optics

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Laws of Reflection and Refraction

There are three laws which govern Reflection and Refraction. These can be very easily derived from geometry.They are:

  • Angle of Incident Ray with Normal(i) EQUALS Reflected Ray with Normal(r).(i=r)
  • Popularly known as SNELL'S LAW it is n1*sin i=n2*sin e where i is same as above,e is angle of refracted beam with normal.
  • The INCIDENT ray,REFLECTED ray, REFRACTED ray and the NORMAL at the point of incidence all lie in the same plane.The plane is referred as plane of incidence.

    • Q. What does the applet do?

    A. The applet would generate an incident ray from the point you click in the UPPER LEFT REGION. The useful details that you will get are

  • Angle of incidence(i)
  • 2.Angle of Reflection(r)
  • 3.Angle of Refraction(e).
  • 4.Critical Angle.
  • 5.A message TOTAL INTERNAL REFLECTION will be displayed whenever such a thing happens.

    • Q. How to use?

    A. Well, that is self explanatory but still...

  • Just keep clicking in the upper left region
  • You can increse or decrease either mediums refractive
  • indices by clicking INC or DEC

    • Q. Important Concepts you would like to know?

    A. Well,i would here like to list the optical concepts that i have utilised in making this applet

  • The above listed laws
  • Critical angle It is the incident angle at which angle of refarction becomes 90 degree.
  • Total Internal Reflection A phenomenon when light incident does not get refracted. The above two phenomenon requires light passing from denser to rarer medium.