Waves: Required Practical - Reflection and Refraction Flashcards
What equipment is needed to carry out an experiment for reflection and refraction?
- ray box
- lens
- slit
- piece of paper
- pencil
- ruler
- protractor
- glass block / other material block
What could be used as an alternative to a ray box? Why is it less commonly used?
Reflection and refraction could be investigated using a laser however that can be more dangerous.
How should you initially set up your piece of paper to investigate reflection and refraction?
- Draw a straight line down the centre using a ruler.
- Use a protractor to draw a line perpendicular to the first straight line.
- Label this the normal line
Where should the glass block be places in relation to the straight line and normal?
It should lie against the first line and with the normal line near the centre of it.
After positioning the glass block on the paper, what should be done?
Draw around the glass block
Once everything had been drawn and positioned on the paper, a ray of light is used. Where should this ray be directed and what is used to produce it?
A ray of light should be directed at block so that it hits it at the normal.
This ray of light is produced using a ray box.
What is the incident ray in this practical?
The ray produced by the ray box before it enters the block is called the incident ray.
What is the angle of incidence?
The angle between the incident ray and the normal.
What is the transmitted ray? What is the reflected ray?
The ray that leaves the block from the opposite side.
The ray that is reflected off the surface of the block.
After shining the light at the block, what should be marked onto the paper using a pencil?
The path of the incident ray reflected ray and transmitted ray.
After removing the glass block, what should be plotted on the paper?
Draw a line to show the incident ray and reflected ray.
Draw a line to show the transmitted ray.
Draw a line to connect the incident ray and transmitted ray and show the path of the light inside the glass block
What are the names of the angles measured? Describe where these are located. What are they measured with?
Angle of incidence
Angle between incident ray and normal.
Angle of reflection
Angle between reflected ray and normal.
Angle of refraction
Angle between normal and path of transmitted ray inside the block.
These should all be measured using a protractor.
Once the experiment is complete, it can be repeated but with some changed independent variables. What is changed for this practical?
The material of the block eg. a plastic such as Perspex
What should be found out about the angles of incidence and reflection after completing this practical using different materials? Why is this?
They are the same for any material.
This is because these angles do not depend on the material.
With a different material, which angle will change?
angle of refraction
