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The following objects are placed one after each other in given order onto a central axis with a separation of 40 cm each. A point source of light O. a diverging lens of focal length 40 cm. a converging lens of focal length 40 cm and converging mirror of focal length 80 cm. The aperture diameter of lenses and mirror is d=20 cm. If a point source of light is placed at a perpendicular distance of x from central axis then. (You have to consider single optical event at any optical element)
Mark the CORRECT statement(s):-

A

Final image is formed in the plane of converging lens

B

If `x gt 1.5d` the rays will not be reflected by converging mirror

C

For `x gt d` final real images can be captured on a screen after on optical event (i.e refraction or reflection)at every optical system

D

Final image is real and inverted

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To solve the problem step by step, we will analyze the optical system consisting of a point source of light, a diverging lens, a converging lens, and a converging mirror. We will calculate the image positions and magnifications for each optical element and determine the validity of the statements provided. ### Step-by-Step Solution: 1. **Identify the Optical Elements and Their Positions:** - Point source of light (O) at position 0 cm. - Diverging lens (focal length = -40 cm) at position 40 cm. - Converging lens (focal length = 40 cm) at position 80 cm. - Converging mirror (focal length = 80 cm) at position 120 cm. 2. **Calculate Image Formed by the Diverging Lens:** - Object distance (u) for the diverging lens: \[ u = -40 \text{ cm} \quad (\text{negative as per sign convention}) \] - Focal length (f) of the diverging lens: \[ f = -40 \text{ cm} \] - Using the lens formula: \[ \frac{1}{f} = \frac{1}{v} - \frac{1}{u} \] Rearranging gives: \[ \frac{1}{v} = \frac{1}{f} + \frac{1}{u} = \frac{1}{-40} + \frac{1}{-40} = \frac{-2}{40} = -\frac{1}{20} \] Thus, \[ v = -20 \text{ cm} \] - The image formed by the diverging lens is at -20 cm (virtual image). 3. **Calculate Image Formed by the Converging Lens:** - Object distance (u) for the converging lens: \[ u = -20 \text{ cm} + 40 \text{ cm} = 60 \text{ cm} \quad (\text{distance from the lens to the image of the diverging lens}) \] - Focal length (f) of the converging lens: \[ f = 40 \text{ cm} \] - Using the lens formula again: \[ \frac{1}{f} = \frac{1}{v} - \frac{1}{u} \] Rearranging gives: \[ \frac{1}{v} = \frac{1}{40} + \frac{1}{-60} = \frac{3 - 2}{120} = \frac{1}{120} \] Thus, \[ v = 120 \text{ cm} \] - The image formed by the converging lens is at 120 cm (real image). 4. **Calculate Image Formed by the Converging Mirror:** - Object distance (u) for the converging mirror: \[ u = 120 \text{ cm} - 40 \text{ cm} = 80 \text{ cm} \] - Focal length (f) of the converging mirror: \[ f = 80 \text{ cm} \] - Using the mirror formula: \[ \frac{1}{f} = \frac{1}{v} + \frac{1}{u} \] Rearranging gives: \[ \frac{1}{v} = \frac{1}{80} - \frac{1}{80} = 0 \] Thus, \[ v = -40 \text{ cm} \] - The final image formed by the converging mirror is at -40 cm (real image). 5. **Determine the Height of the Final Image:** - The magnification for the diverging lens: \[ m_1 = \frac{v}{u} = \frac{-20}{-40} = \frac{1}{2} \] - The magnification for the converging lens: \[ m_2 = \frac{v}{u} = \frac{120}{60} = 2 \] - The total magnification (M) is: \[ M = m_1 \times m_2 = \frac{1}{2} \times 2 = 1 \] - Therefore, the height of the final image is equal to the height of the object (x). 6. **Check the Conditions for the Statements:** - **Statement A:** The final image is real and inverted, which is correct. - **Statement B:** If \( x > 1.5d \) (where \( d = 20 \text{ cm} \)), the rays will not be reflected by the converging mirror. This is correct since \( 1.5d = 30 \text{ cm} \). - **Statement C:** If \( x > d \), the final real images can be captured on a screen after every optical event. This is incorrect because the diverging lens produces a virtual image. ### Conclusion: The correct statements are A and B.

To solve the problem step by step, we will analyze the optical system consisting of a point source of light, a diverging lens, a converging lens, and a converging mirror. We will calculate the image positions and magnifications for each optical element and determine the validity of the statements provided. ### Step-by-Step Solution: 1. **Identify the Optical Elements and Their Positions:** - Point source of light (O) at position 0 cm. - Diverging lens (focal length = -40 cm) at position 40 cm. - Converging lens (focal length = 40 cm) at position 80 cm. ...
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