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A plane mirror 50 cm long, is hung on a ...

A plane mirror `50 cm` long, is hung on a vetical wall of a room, with its lower edge `50 cm` above the ground. `A` man stands of the mirror at a distance `2 m` away from the mirror. If his eyes are at a height `1.8 m` above the ground, then the length (distance between the extreme points of the visible region perpendicular to the mirror ) of the floor visible to him due to refliection from the mirror is `(x)/(26)m` . Find the value of `x`

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To solve the problem step by step, we will analyze the situation involving the plane mirror, the man, and the heights involved. ### Step 1: Understand the setup - The plane mirror is 50 cm long and its lower edge is 50 cm above the ground. - The man stands 2 m away from the mirror, and his eyes are at a height of 1.8 m above the ground. ### Step 2: Identify the relevant points - Let’s denote: - The bottom edge of the mirror as point O (50 cm above the ground). - The top edge of the mirror as point S (50 cm + 50 cm = 100 cm above the ground). - The height of the man's eyes as point E (1.8 m = 180 cm above the ground). ### Step 3: Calculate the height of the visible region - The visible region on the floor due to the reflection in the mirror can be determined by finding the points on the ground that correspond to the reflection of the man's eyes in the mirror. ### Step 4: Use similar triangles - The triangles formed by the eye level and the mirror can be analyzed. - The height of the eye level (E) is 1.8 m (or 180 cm), and the height of the bottom of the mirror (O) is 0.5 m (or 50 cm). - The height of the top of the mirror (S) is 1 m (or 100 cm). ### Step 5: Calculate the distances - The distance from the eye level to the bottom of the mirror (O) is: \[ EM = 1.8 \, \text{m} - 0.5 \, \text{m} = 1.3 \, \text{m} \] - The distance from the eye level to the top of the mirror (S) is: \[ ES = 1.8 \, \text{m} - 1.0 \, \text{m} = 0.8 \, \text{m} \] ### Step 6: Set up the ratios using similar triangles - For the triangle formed by the eye level and the bottom of the mirror: \[ \frac{EM}{PO} = \frac{MP}{OS} \] where \( PO = 2 \, \text{m} \) (distance from the man to the mirror). - For the triangle formed by the eye level and the top of the mirror: \[ \frac{EN}{QR} = \frac{OQ}{RO} \] ### Step 7: Solve for the lengths - Using the ratios, we can find the lengths: - For \( OS \): \[ OS = \frac{MP \cdot PO}{EM} = \frac{2 \cdot 1}{1.3} = \frac{20}{13} \, \text{m} \] - For \( OR \): \[ OR = \frac{OQ \cdot QN}{EN} = \frac{0.5 \cdot 2}{1.3} = \frac{10}{13} \, \text{m} \] ### Step 8: Calculate the visible length - The visible length of the floor is given by: \[ Visible \, Length = OS - OR = \frac{20}{13} - \frac{10}{13} = \frac{10}{13} \, \text{m} \] ### Step 9: Convert to the required format - The problem states that the visible length is given as \( \frac{x}{26} \, \text{m} \). - Setting \( \frac{10}{13} = \frac{x}{26} \): \[ x = \frac{10 \cdot 26}{13} = 20 \] ### Final Answer The value of \( x \) is **20**.

To solve the problem step by step, we will analyze the situation involving the plane mirror, the man, and the heights involved. ### Step 1: Understand the setup - The plane mirror is 50 cm long and its lower edge is 50 cm above the ground. - The man stands 2 m away from the mirror, and his eyes are at a height of 1.8 m above the ground. ### Step 2: Identify the relevant points - Let’s denote: ...
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RESONANCE ENGLISH-GEOMATRICAL OPTICS -Exercise-2
  1. STATEMENT -1: A white parallel beam of light is incident on a plane gl...

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  2. A fluorescent lamp of length 1m is placed horizontally at a depth of 1...

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  3. A plane mirror 50 cm long, is hung on a vetical wall of a room, with i...

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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