Embedded Files
Chapter 18: Laboratory Investigations
Chapter 18: Laboratory Investigations
There are five mini-laboratory investigations in chapter 18. Look though each lab and make observations and conclusions using the pictures given, then answer the questions for each lab on the reflection lab laboratory investigation found in google classroom.
Laboratory Equipment for All Labs
Laboratory Equipment for All Labs
This Light Box and Optical Set makes it easy to perform experiments involving the optics of lenses, mirrors, and prisms, as well as providing a versatile way to display primary and secondary colors; and both additive and subtractive color mixing. The double-ended light box contains a halogen lamp powered by a wall-mount AC adapter and cooled by a built-in fan. One end carries a cylindrical lens and slots for mounting the three slit diaphragms for ray optics. The other end carries two adjustable mirrors and an open area for color mixing and subtraction.
This set comes with an assortment of lenses, prisms, acrylic blocks, mirrors, slit plates, color filters, and color paddles that we will be using for laboratory investigations in chapters 16, 17, and 18.
We will not be using the adjustable mirror side for these labs.
Lab: How Does Light Refract?
Lab: How Does Light Refract?
Objective:
To learn how light is bent when it passes from air into Plexiglas.
Procedure and Observations :
The power supply has been plugged in and we are using the end of the light box without the swinging doors. The single-slit mask was used. The light box was set up so the line of light was pointed towards point O, along the normal line. The light box was moved so the ray is along line AO. A sharpened pencil was used to mark the path of light that comes out of the block. The light was adjusted so that the light ray was aligned with the other rays.
The plastic block was removed. A best fit line was drawn for each of the refracted rays starting at point O. Use the protractor on the picture to measure each angle of incidence and the corresponding angle of refraction for each ray. Remember to measure all the angles from the normal line - each angle should be under 90º. Record your measurements in the data table on your lab.
Light Along A
Light Along A
Light Along B
Light Along B
Light Along C
Light Along C
Light Along D
Light Along D
Light Along E
Light Along E
All Rays Drawn on One Paper
All Rays Drawn on One Paper
Measuring the Angles of Incidence
Measuring the Angles of Incidence
Remember, all angles are less than 90º.
Measuring the Angle of Refraction
Measuring the Angle of Refraction
The refracted rays were redrawn straight so they did not bend again when exiting the half round plastic. This will allow you to read the angles right from the protractor. Remember, all angles are less than 90º.
Lab: When is Light Reflected Internally?
Lab: When is Light Reflected Internally?
Objective:
To learn how light is bent when it passes from Plexiglas into air.
Procedure and Observations :
The power supply has been plugged in and we are using the end of the light box without the swinging doors. The single-slit mask was used. The light box was set up so the line of light was pointed towards point O, along the normal line. The light box was moved so the ray is along line AO. A sharpened pencil was used to mark the path of light that comes out of the block. The light was adjusted so that the light ray was aligned with the other rays.
The plastic block was removed. A best fit line was drawn for each of the refracted rays starting at point O. Use the protractor on the picture to measure each angle of incidence and the corresponding angle of refraction for each ray. Remember to measure all the angles from the normal line - each angle should be under 90º. Record your measurements in the data table in your lab.
Light Along A
Light Along A
Light Along B
Light Along B
Light Along C
Light Along C
Light Along D
Light Along D
Light Along E
Light Along E
All Rays Drawn on One Paper
All Rays Drawn on One Paper
Measuring the Angles of Incidence
Measuring the Angles of Incidence
Remember, all angles are less than 90º.
Measuring the Angle of Refraction
Measuring the Angle of Refraction
If the light did not refract, and was reflected internally, there is NO angle of refraction, sine of the angle of refraction, or ratio of the sines.
When there is an angle of refraction, it is less than 90º.
Lab: How is Light Refracted Through a Transparent Block?
Lab: How is Light Refracted Through a Transparent Block?
Objective:
To learn how light is bent when it travels through a Plexiglas block.
Procedure and Observations :
The power supply has been plugged in and we are using the end of the light box without the swinging doors. The single-slit mask was used. The light box was set up so the line of light was pointed along the light ray direction and the plexiglas block was placed in the three different positions, Figures 1-3.
Figure 1
Figure 1
Figure 2
Figure 2
Figure 3
Figure 3
Question #3 - Figure 3
The normal lines were drawn at the point of entry for the light ray, the angle of incidence was measured and recorded on the drawing. The angle of refraction was measured and recorded on the drawing. Compute the ratio of sines. This ratio is called the index of refraction.
Lab: How is Light Refracted Through a Prism?
Lab: How is Light Refracted Through a Prism?
Objective:
To learn how light is bent when it passes through prisms.
Procedure and Observations :
The power supply has been plugged in and we are using the end of the light box without the swinging doors. The single-slit mask was used. The light box was set up so the line of light was pointed along the light ray direction and three different plexiglas prisms, Figures 4-6.
Figure 4
Figure 4
Figure 5
Figure 5
Figure 6
Figure 6
Lab: How is Light Bent When it Passes Through a Half-Round Lens?
Lab: How is Light Bent When it Passes Through a Half-Round Lens?
Objective:
To learn how light is bent when it passes through a half round lens.
Procedure and Observations :
The power supply has been plugged in and we are using the end of the light box without the swinging doors. The four-slit mask was used. The light box was set up so the line of light was pointed along the light ray direction and the half round lens was placed on the diagram, Figure 7.
The half round lens was flipped around and the four-slit mask was used. The light box was set up so the line of light was pointed along the light ray direction and the half round lens was placed on the diagram, Figure 8.
Figure 7
Figure 7
Figure 8
Figure 8
During the Next Class Period:
During the Next Class Period:
Report abuse