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A buring candle is placed in front of a ...

A buring candle is placed in front of a concave spherical mirror on its principal optical axis at a distance of `(4//3)F` form the pole of the mirror (here `F` is the focal length of the mirror). The candle is arranged at right angle to the axis. The image of the candle in the concave mirror impinges upon a convex mirror of focal length `2F` . The distance between the mirrors is `3F` and their axes coincide. The image of the candle in the first mirror plays the part of a virtual object with respect to the second mirror and gives a real image arranged between the two mirrors. Find the total linear magnification (magnitude only) of the system.

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To solve the problem step by step, we will analyze the situation involving the concave mirror and the convex mirror. ### Step 1: Understand the setup We have a burning candle placed at a distance of \( \frac{4}{3}F \) from the pole of a concave mirror. The focal length \( F \) is considered negative for concave mirrors. ### Step 2: Apply the mirror formula for the concave mirror The mirror formula is given by: \[ \frac{1}{f} = \frac{1}{v} + \frac{1}{u} \] For the concave mirror: - Focal length \( f = -F \) - Object distance \( u = -\frac{4}{3}F \) (negative because the object is in front of the mirror) Substituting these values into the mirror formula: \[ -\frac{1}{F} = \frac{1}{v} - \frac{3}{4F} \] Rearranging gives: \[ \frac{1}{v} = -\frac{1}{F} + \frac{3}{4F} = -\frac{4}{4F} + \frac{3}{4F} = -\frac{1}{4F} \] Thus, we find: \[ v = -4F \] ### Step 3: Calculate the magnification for the concave mirror The magnification \( m_1 \) for the concave mirror is given by: \[ m_1 = -\frac{v}{u} \] Substituting the values we found: \[ m_1 = -\frac{-4F}{-\frac{4}{3}F} = -\frac{4F}{\frac{4}{3}F} = -3 \] ### Step 4: Determine the virtual object for the convex mirror The distance between the two mirrors is \( 3F \). The image formed by the concave mirror acts as a virtual object for the convex mirror. The object distance \( u \) for the convex mirror is calculated as: \[ u = 3F - |v| = 3F - 4F = -F \] (Note: The negative sign indicates that the object is virtual and located on the same side as the object for the convex mirror.) ### Step 5: Apply the mirror formula for the convex mirror For the convex mirror: - Focal length \( f = +2F \) - Object distance \( u = -F \) Using the mirror formula: \[ \frac{1}{f} = \frac{1}{v} + \frac{1}{u} \] Substituting the values: \[ \frac{1}{2F} = \frac{1}{v} - \frac{1}{F} \] Rearranging gives: \[ \frac{1}{v} = \frac{1}{2F} + \frac{1}{F} = \frac{1}{2F} + \frac{2}{2F} = \frac{3}{2F} \] Thus, we find: \[ v = \frac{2F}{3} \] ### Step 6: Calculate the magnification for the convex mirror The magnification \( m_2 \) for the convex mirror is given by: \[ m_2 = -\frac{v}{u} \] Substituting the values: \[ m_2 = -\frac{\frac{2F}{3}}{-F} = \frac{2}{3} \] ### Step 7: Calculate the total magnification The total magnification \( m \) of the system is the product of the magnifications of the two mirrors: \[ m = m_1 \times m_2 = (-3) \times \left(\frac{2}{3}\right) = -2 \] In magnitude, the total linear magnification is: \[ |m| = 2 \] ### Final Answer The total linear magnification (magnitude only) of the system is: \[ \boxed{6} \]

To solve the problem step by step, we will analyze the situation involving the concave mirror and the convex mirror. ### Step 1: Understand the setup We have a burning candle placed at a distance of \( \frac{4}{3}F \) from the pole of a concave mirror. The focal length \( F \) is considered negative for concave mirrors. ### Step 2: Apply the mirror formula for the concave mirror The mirror formula is given by: \[ ...
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RESONANCE ENGLISH-GEOMATRICAL OPTICS -Exercise-2
  1. A plane mirror 50 cm long, is hung on a vetical wall of a room, with i...

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  2. A light ray I is incident on a plane mirror M. The mirror is rotated i...

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  3. A buring candle is placed in front of a concave spherical mirror on it...

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  4. A concave mirror forms real image of a point source lying on the optic...

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  5. A concave mirror of focal length 10cm and a convex mirror of focal len...

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  6. The x-y plane is the boundary between two transparent media. Medium-1 ...

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  7. (a) In the figure shown a slab of refractive index (3)/(2) is moved to...

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  8. Mirror in the arrangement shown in figure is moving up with speed 8 cm...

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  9. A point object is placed on principal axis of a concave mirror of radi...

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  10. Light is incident from glass to are. The variation of the angle of dev...

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  11. A hemispherical portion of the surface of a solid glass sphere (mu = 1...

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  12. In the figure, a point object O is placed in air. A spherical boundry ...

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  13. A glass hemispher of refractive index 4//3 and of radius 4 cm is place...

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  14. A converging lens of focal length 15 cm and a converging mirror of foc...

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  15. An object of height h(0)=1 cm is moved along principal axis of a conve...

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  16. Object O is kept in air in fron of a thin plano convex lens of radius ...

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  17. A symmetrical converging convex lens of focal length 10 cm & diverging...

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  18. An object O is kept in air and a lens of focal length 10 cm (in air) i...

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  19. A stationary observer O looking at a fish (in water of mu=4//3 ) throu...

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  20. The dispersive power of the material of a lens is 0.04 and the focal l...

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