JP6582613B2 - Light refraction experimental template - Google Patents

Description

In the light refraction experiment using the light refraction experiment template, the vertical and horizontal lines characteristic of each of the three templates are printed, the angle of incident light is set in the first template, and the three horizontal lines are Based on the principle of intersecting at one point, when the second template is put together, the path of the refracted light is determined and appears at an actual angle on the template, so that the experiment changes from a qualitative experiment to a quantitative experiment. The present invention relates to a template for light refraction experiments that can be expected to improve quality.

The conventional light refraction experimental device has an angle scale on a circular water tank, measures the angle of incident light and the angle of refracted light with the scale, and confirms that the light refraction phenomenon has occurred by looking at the difference in angle. I stayed in. Even when the study was advanced a little, the ratio of the sine of the incident angle to the sine of the refraction angle showed a constant value, and it was only completed by understanding that it was called the refractive index.

The challenge is to easily determine the incident angle and refraction angle at which the ratio of the sine of the incident angle and the sine of the refraction angle is equal to the refractive index by matching the three templates so that the three horizontal lines intersect at one point.
A problem that simply explains that a refraction phenomenon appears from the difference in the speed of light per unit time from a figure where three horizontal lines intersect at one point.

A template 1 in which a vertical diameter line 2, a horizontal diameter line 3, and an angle scale 4 are printed on a circular transparent resin plate, and a vertical radius line 6 on the circular transparent resin plate, and a line segment 8 in the direction of the vertical radius line 6 from the center. set, and printing the end point by Rimizu Tairasen 7, the template 5 and the circular transparent resin plate, the vertical radius line 10, on the extension of the vertical radial line 10 from the center, 1 / refractive index with respect to the line segment 8 a line segment 12 having a length set for the argument, the template 9 printed with horizontal line 11 from its end point, overlapping the three pieces of template 1, 5 and 9, in eyelet or the like by performing a hole in the circular center When the three templates 1, 5, 9 can be freely rotated and the direction of the incident light is aligned with the vertical radius line 6 and the direction of the refracted light is aligned with the vertical radius line 10, the three horizontal lines 3, 7, 11 meet at one point. At the time of implementation , the template 1 is fixed to the water tank, and the movable templates are 5 and 9. (Fig. 4)

When the vertical radial line 6 is aligned with the incident light from an arbitrary direction and the three horizontal lines 3, 7 and 11 intersect at one point, the vertical radial line 10 determines and displays the path of the refracted light.

The principle of the means for solving the problem will be briefly described. In FIG. 5 in which the core part of FIG. 4 is extracted, the right triangle 18 and the right triangle 19 have a common hypotenuse 17, and when the length is 1, the sine of the incident light at the angle 15 is the length of the line segment 8. Is equal to the length of the line segment 12. The length ratio between the line segment 8 and the line segment 12 is set in advance equal to the refractive index. Thus, the sine of the incident angle divided by the sine of the refraction angle is equal to the refractive index. It solves what is called Snell's principle.
Moving the right triangle 19 to the position of the right triangle 20 in FIG. 6 does not change the essence of the figure. By drawing a straight line 13 parallel to the incident light 6 and a straight line 14 parallel to the refracted light 10, in FIG. 5 and FIG. FIG. 6 clearly illustrates that the refraction phenomenon occurs as the distance of the minute 12 is advanced.

FIG. 7 relates to claim 3. If the template 5 is changed to the template shown in FIG. 7, the refractive index can be read directly. FIG. 8 shows an example when the refractive index can be directly read as 1.4.

By applying the template as shown in FIG. 4 to the apparatus as shown in FIG. 9, it can be understood that the refraction of light follows Snell's principle, the light path is clearly shown by this principle, and the qualitative experiment Has evolved into a classic experiment. When the incident angle is given, the refraction angle can be immediately determined on the figure. On the other hand, the light refraction experiment, which was handled in junior high school and high school in science education, can be applied to science teaching materials in elementary school if it is taught that the light travels behind in water. FIG. 6 is considered to be understood by elementary school students.
A method for determining the incident angle and the refraction angle clearly according to Snell's principle by determining the directions of the incident light and the refraction light on a rotatable template has not been found so far.

  Template with angle scale for measuring incident angle of incident light and refraction angle of refracted light   Template that aligns the axis with the incident direction of incident light   Template that aligns the axis with the direction of refraction   A diagram explaining how to use the three templates by overlapping the centers and fixing them with eyelets   Diagram explaining the relationship between sine of incident angle, sine of refraction angle, and refractive index   Diagram explaining the refraction phenomenon from the difference between the speed of light in the air and the speed of light in the water, for example   Refractive index can be read directly   As an example, the figure when the refractive index can be read as 1.4   Schematic of relationship between aquarium and light source when using template

FIG. 9 is a schematic diagram for explaining the effect of the invention, and a mode for carrying out the invention will be described with reference to FIG. In FIG. 4, it is desirable that the three-layered templates are stacked in the order of the template 5 in FIG. 2 and the template 9 in FIG. 3 below the template 1 in FIG. A handle portion of the template 1 is fixed with a tape or the like in a water tank in which a light source is prepared. In this case, the water line must be aligned with the horizontal diameter line 3. Next, the direction of incident light from the light source is determined, and the vertical radius line 6 of the template 5 is aligned with that direction. Next, the template 9 is rotated, the horizontal line 11 is intersected at the intersection of the horizontal diameter line 3 and the horizontal line 7, and it is confirmed that the three horizontal lines 3, 7, 11 intersect at one point. It can be confirmed that the direction of the refracted light coincides with the direction of the vertical radius line 10.
Similarly, an experiment of refracted light from water to air can be performed by providing a light source underneath and applying incident light from water. As a specific example, when the vertical radius line 6 is matched with the horizontal diameter line 3 in advance, the template 9 is rotated, and it is determined that the three horizontal lines 3, 7, and 11 intersect at one point, the direction of the vertical radius line 10 can be seen. The incident angle represents the critical refraction angle.

1 Scaled template for measuring incident angle of incident light and refracted light 2 Vertical diameter line as a starting point for measuring the angle of incident light and refracted light 3 Boundary horizontal line for distinguishing incident light side and refracted light side, horizontal diameter Line 4 Scale line for measuring the angle of incident light and refracted light 5 Template used by aligning the vertical radial line with the direction of incident light Vertical radius line 7 for aligning with the direction of incident light Vertical on the incident light side and related to the refraction principle A straight line that is horizontal to the radius line,
8 A line segment whose length corresponds to the speed of light in the air 9 A template that uses a vertical radial line that matches the direction of the refracted light 10 A vertical radial line that matches the direction of the refracted light 11 A straight line 12 that is horizontal to the vertical radius line concerned, and whose length corresponds to the speed of light in water (eg, 0.75 times the line 8 for water)
13 Auxiliary additional straight line 14 parallel to the direction of the incident light 14 Auxiliary additional straight line 15 parallel to the direction of the refracted light 15 Representing the incident angle 16 Representing the refraction angle 17 Common hypotenuse 18 of the two right triangles 18 and 19 The right triangle 19 related to the refracted light The right triangle related to the refracted light The right triangle related to the refracted light with the position of the right triangle 19 reversed.

Claims (3)

Circular transparent resin plate, a horizontal diameter line 3 was printed, the template 1 processing the handle,
On the circular transparent resin plate, a vertical radius line 6, a horizontal line 7 drawn from an end point of a line segment 8 set in the direction of the vertical radius line 6 from the center, and a template 5 in which a handle is processed,
On the circular transparent resin plate, a template 9 in which a vertical radius line 10 and a horizontal line 11 drawn from an end point of a line segment 12 set on the extension of the vertical radius line 10 from the center are printed and a handle is processed ,
With
A hole is made in the center of these three templates 1, 5, 9, and the three templates are stacked and fixed with eyelets, etc., so that each template can rotate freely ,
With respect to the horizontal diameter line 3 of the template 1, the vertical radius line 6 of the template 5 is matched with the incident light, the vertical radius line 10 of the template 9 is matched with the path of the refracted light, and the lengths of the line segments 8 and 12 are set. A template for light refraction experiment that can set the horizontal diameter line 3, the horizontal line 7, and the horizontal line 11 to intersect at one point by setting . 2. A template for light refraction experiment according to claim 1, wherein the ratio of the length of the line segment 8 of the template 5 to the length of the line segment 12 of the template 9 is set to 1: 1 / n, where n is the refraction light side material. Refractive index. The ratio of the length of the line segment 8 of the template 5 and the line segment 12 of the template 9 is 1: 1 / 1.0, 1: 1 / 1.2, 1: 1 / 1.4, 1: 1/1. .6, 1: 1 / 1.8, 1: 1/2. Six set to 0, or more numbers refractive experimental template of light based on claim 1 which enables the refractive index direct reading minus the horizon.

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