Rays Passing Through a Glass Block are Refracted Twice Flashcards
How can you experiment with refraction?
Using a light source and a rectangular block of a particular material (e.g glass) resting on top of a piece of paper…
What do you do first?
Shine a light ray at an angle into the block.
What happens (after step 1)
Some of the light is reflected, but a lot of it passes through the glass and gets refracted as it does so
What do you do second?
Trace the incident and emergent rays onto the piece of paper and remove the block
How can you draw in the refracted ray through the block?
By joining the ends of the other two rays with a straight line
What happens as the light passes from the air into the block? ( a denser medium )
It bends towards the normal because it slows down
What happens when the light reaches the boundary on the other side of the block?
It’s passing into a less dense medium, so it speeds up and bends away from the normal
What is the light ray that emerges on the other side of the block now doing?
Travelling in the same direction it was to begin with
What does this mean has happened to it?
It’s been refracted towards the normal and then back again by the same amount
Look at the diagram on page 33
Ok
