3b-scientific Light Box Manuel d'utilisateur

1LIGHT BOX & OPTICAL SET Contents • 1 Light Box • 1 set of 8 color cards • 1 Plane mirror •

10 Displacement, Parallel-sided Slab: In the previous experiment, ‘d’ in the diagram is the displacement of the emergent ray. For a giv

11µ of the slab can also be found by the apparent depth method. µ = real depth/apparent depth. (This is strictly true only when i1 is close to 90°)

12 The refractive index of the slab is calculated by iirsin1sinsin==µ The ∠i at this point is called the CRITICAL ANGLE of the medium

13 The other prisms can also be experimented with. Try to obtain at least five positions of the three prisms (besides the above two), which

14 Dispersion of Colors: Allow a wide beam of light to be incident on one face of the equilateral prism. On a white screen, observe the emergent spec

15Focus - Concave Lens: Allow a set of parallel rays to fall on the concave lens parallel to its axis of symmetry. The rays diverge after refraction.

16Spherical Aberration: Allow four parallel rays to strike a convex lens, parallel to its axis of symmetry. The inner two and outer two rays meet at

17In the set-up for spherical aberration, block the two inner rays and observe the colored foci obtained closely. • Which color has the shortest f

18concave lens. The procedure is to focus the rays from the source by means of the lens, O1, and to locate the image, F. The concave lens is then pla

19 Method 3: Set up a concave mirror behind the lens and a pin in front. An inverted image of the pin will be seen on looking through the lens, and i

2The optical devices (mirrors, lenses, prisms, slabs) should be handled by their finger-grips, so that no smudges or scratches are inadvertently left

20rays, which affect the eyes the most, come in between. A screen placed so as to catch the yellow focus would show an image with a purple border, th

3Color of filter used → Color of plate in white light ↓ W R M O Y G C B V R M O Y G C V

42. The incident ray, normal ray and reflected ray, all lie in the same plane. Besides these laws, there are other important features of reflection

5Similarly, if you place the mirror on the dotted line and look at the image of the word below from the bottom of the page, what do you see?

6 Rotation of a Plane Mirror: Aim a single ray at the mirror and note the incident ray, mirror position and reflected ray. Rotate the mirror slightly

7 • Are the angles of incidence equal to the angles of reflection? The above problem of improper focusing can be resolved by using a Par

8 • Place a convex lens (of short focal length) in front of the slits and adjust the convex mirror beyond it until the reflected rays coi

9times) until the emergent ray is not deflected. Mark the point of incidence - this is the center of curvature. Shift the light-box so that a single