Class name Subject Book title Chapter number Content Created at
Class XII Physics Physics Part-II 1  1 1  =(n−1 ) −  12 10 −15  This gives n = 1.5. (iii) For a glass lens in air, n = 1.5, n = 1, f = +20 cm. Hence, the lens 2 1 formula gives ...
Class XII Physics Physics Part-II 1 Adding Eqs. (9.27) and (9.28), we get 1 1 1 1 v − u = f + f (9.29) 1 2 If the two lens-system is regarded as equivalent to a single lens of focal l...
Class XII Physics Physics Part-II 1 we get r1+ r2= A (9.34) The total deviationd is the sum of deviations at the two faces, d= (i – 1 ) + (e 2 r ) that is, d = i + e – A (9.35) Thus, ...
Class XII Physics Physics Part-II 1 m 21 It implies that, thin prisms do not deviate light much. 9.7 O PTICAL INSTRUMENTS A number of optical devices and instruments have been designe...
Class XII Physics Physics Part-II 1 near point (distance D @ 25 cm), it causes some strain on the eye. Therefore, the image formed at infinity is often considered most suitable for vi...
Class XII Physics Physics Part-II 1 by the image when the object is at u. From the relations h′ = m = v h u we have the angle subtended by the image h′ h v h tan θi= = ⋅ = » q. The an...
Class XII Physics Physics Part-II 1 the refractive index of the material of the prism? The refracting angle of the prism is 60°. If the prism is placed in water (refractive index 1.33...
Class XII Physics Physics Part-II 1 closer for image formation at the near point. Clearly, m p l s the final image is inverted with respect to the original object. We now obtain the m...
Class XII Physics Physics Part-II 1 In practice, it is difficult to make the focal length much smaller than 1 cm. Also large lenses are required to make L large. For example, with an ...
Class XII Physics Physics Part-II 1 whose objective has a focal length of 100 cm and the eyepiece a focal length of 1 cm. The magnifying power of this telescope is m = 100/1 = 100. Le...
Class XII Physics Physics Part-II 1 2026-27 Physics FIGURE 9.26 Schematic diagram of a reflecting telescope (Cassegrain). the telescope tube. One must have an eyepiece and the observe...
Class XII Physics Physics Part-II 1 eyepiece of focal length 2.5cm can bring an object placed at 9.0mm from the objective in sharp focus. What is the separation between the two lenses...
Class XII Physics Physics Part-II 1 material of lower refractive index. Light incident at an angle at one end comes out at the other, after multiple internal reflections, even if the ...
Class XII Physics Physics Part-II 1 unit for power of a lens is dioptre (D): 1 D = 1 m .–1 If several thin lenses of focal length f 1 f 2 f3,.. are in contact, the effective focal len...
Class XII Physics Physics Part-II 1 between f and 2f from a convex lens can be seen on a screen placed at the image location. If the screen is removed, is the image still there? This ...
Class XII Physics Physics Part-II 1 of curvature 36 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Describe the nature and size of th...
Class XII Physics Physics Part-II 2 the smallness of the wavelength of visible light (in comparison to the dimensions of typical mirrors and lenses), light can be assumed to approxima...
Class XII Physics Physics Part-II 2 magnetic fields result in the propagation of electromagnetic waves (or light waves) even in vacuum. In this chapter we will first discuss the origi...
Class XII Physics Physics Part-II 2 are then the locus of points which have the same amplitude and vibrate in spherical. the same phase are spheres and we have what is known as a sphe...
Class XII Physics Physics Part-II 2 the shape of the wavefront at t = , we draw spheres of radius v from each point on the spherical wavefront where v represents the speed of the wave...
Class XII Physics Physics Part-II 2 A A incident on the interface at an angle i as shown in the represent rays. figure. Let be the time taken by the wavefront to travel the distance B...
Class XII Physics Physics Part-II 2 refraction shown by the E 1 mineral calcite in this N the corpuscular model of light and as later experiments work in addition to S showed, the pre...
Class XII Physics Physics Part-II 2 define an angle i by the following equation e 1 2 c p n 2 o sinic= (10.8) D n 1 d Thus, if i = i then sin r = 1 and r = 90°. Obviously, for i > i ,...
Class XII Physics Physics Part-II 2 MN. AB and CE represent incident and reflected wavefronts. If we now consider the triangles EAC and BAC we will find that they are congruent and th...
Class XII Physics Physics Part-II 2 the ray going through the centre traverses a shorter path, but because of the slower speed in glass, the time taken is the same as for rays travell...