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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

Height of final image is `(x)/(2)`

B

Height of final image is `(x)/(3)`

C

Image formed by converging lens is real and inverted

D

Image formed by converging mirror is real

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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 heights and their nature as the light passes through each optical element. ### Step 1: Analyze the Diverging Lens - **Given**: Focal length \( f_1 = -40 \) cm (negative for diverging lens). - **Object Distance**: \( u_1 = -40 \) cm (the object is placed at the focal point). Using the lens formula: \[ \frac{1}{f} = \frac{1}{v} - \frac{1}{u} \] We rearrange it to find \( v_1 \): \[ \frac{1}{v_1} = \frac{1}{f_1} + \frac{1}{u_1} \] Substituting the values: \[ \frac{1}{v_1} = \frac{1}{-40} + \frac{1}{-40} = -\frac{1}{20} \] Thus, \[ v_1 = -20 \text{ cm} \] - **Nature of Image**: Virtual (since \( v_1 \) is negative). - **Magnification**: \[ M_1 = \frac{v_1}{u_1} = \frac{-20}{-40} = \frac{1}{2} \] ### Step 2: Analyze the Converging Lens - **Given**: Focal length \( f_2 = 40 \) cm. - **Object Distance**: The image from the diverging lens acts as the object for the converging lens. The distance from the diverging lens to the converging lens is 40 cm, so: \[ u_2 = -20 + 40 = -60 \text{ cm} \] Using the lens formula: \[ \frac{1}{v_2} = \frac{1}{f_2} + \frac{1}{u_2} \] Substituting the values: \[ \frac{1}{v_2} = \frac{1}{40} + \frac{1}{-60} \] Finding a common denominator: \[ \frac{1}{v_2} = \frac{3 - 2}{120} = \frac{1}{120} \] Thus, \[ v_2 = 120 \text{ cm} \] - **Nature of Image**: Real (since \( v_2 \) is positive). - **Magnification**: \[ M_2 = \frac{v_2}{u_2} = \frac{120}{-60} = -2 \] ### Step 3: Analyze the Converging Mirror - **Given**: Focal length \( f_3 = -80 \) cm (negative for a converging mirror). - **Object Distance**: The image from the converging lens acts as the object for the mirror. The distance from the converging lens to the mirror is 40 cm, so: \[ u_3 = 120 - 40 = 80 \text{ cm} \] Using the mirror formula: \[ \frac{1}{f_3} = \frac{1}{v_3} + \frac{1}{u_3} \] Rearranging gives: \[ \frac{1}{v_3} = \frac{1}{f_3} - \frac{1}{u_3} \] Substituting the values: \[ \frac{1}{v_3} = \frac{1}{-80} - \frac{1}{80} = -\frac{2}{80} = -\frac{1}{40} \] Thus, \[ v_3 = -40 \text{ cm} \] - **Nature of Image**: Virtual (since \( v_3 \) is negative). - **Magnification**: \[ M_3 = \frac{v_3}{u_3} = \frac{-40}{80} = -\frac{1}{2} \] ### Step 4: Calculate Total Magnification The total magnification \( M \) is given by: \[ M = M_1 \times M_2 \times M_3 \] Substituting the values: \[ M = \frac{1}{2} \times (-2) \times \left(-\frac{1}{2}\right) = \frac{1}{2} \] ### Step 5: Final Image Height If the height of the object is \( h_0 = x \): \[ h = M \times h_0 = \frac{1}{2} \times x = \frac{x}{2} \] ### Conclusion The height of the final image is \( \frac{x}{2} \).

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 heights and their nature as the light passes through each optical element. ### Step 1: Analyze the Diverging Lens - **Given**: Focal length \( f_1 = -40 \) cm (negative for diverging lens). - **Object Distance**: \( u_1 = -40 \) cm (the object is placed at the focal point). Using the lens formula: \[ ...
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