Free help with homework

Why join Brainly?

  • ask questions about your assignment
  • get answers with explanations
  • find similar questions

Why does a beam of light bend when it enters glass at an angle ? why does it not bend if it enters the glass slab at right angles ?



the beam of light deviates  while moving from its path when it enters a glass slab due to refraction, which is caused due to the difference in the velocity of light in different medium due difference in densities.

the light does not bend if it enters at right angles because according to the Snell's law: μ=sin i/sin r
       when angle of incidence is 0⇒sin 0=0
⇒sin r=0/μ
⇒sin r=0⇒ angle of refraction is ⇒0°.
So there is no shift in the path of light and the light passes through undeviated
2 4 2
The light when enters the glass at an angle it bends due the phenomenon called refraction. Due to change of medium the phase velocity of light  changes . this is governed by law which states sinФi/sinФr=vi/vr.
when light is perpendicular sinФi is zero
Since the incident angle is 0 the angle of refraction is also zero.
Though the speed of light reduces in glass medium this can not be noticed.
0 0 0
The Brain
  • The Brain
  • Helper
Not sure about the answer?
Learn more with Brainly!
Having trouble with your homework?
Get free help!
  • 80% of questions are answered in under 10 minutes
  • Answers come with explanations, so that you can learn
  • Answer quality is ensured by our experts