Physics
Light and Mirrors
458 Questions
Light and mirrors questions cover the principles of reflection, image formation, and mirror magnification. Concepts include the properties of plane mirrors, the uses of concave mirrors in solar devices, and the behavior of light rays. These fundamentals are essential general science topics in major competitive examinations.
Plane mirror propertiesConcave mirror applicationsMirror magnification formulaLight reflection lawsImage formation
Light and Mirrors Questions
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Plain
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Convex
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Concave
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Spherical
B
Correct answer
Explanation
Convex mirrors are used as rear-view mirrors because they provide a wider field of view and always form virtual, erect, and diminished images. This allows drivers to see larger area behind. Concave mirrors magnify, and plane mirrors don't widen the field.
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diminished
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enlarged
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same hight
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none of the above
A
Correct answer
Explanation
Convex mirrors curve outward, causing light rays to diverge. This creates images that are always virtual (cannot be projected), erect (upright), and diminished (smaller than the object), regardless of the object's position.
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light is absorbed
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light is diffracted
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light is reflected
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light is refracted
C
Correct answer
Explanation
You see your reflection in a mirror because light is reflected off the smooth surface at the same angle it arrives. Light is NOT absorbed (A - that would make the mirror appear black), diffracted (B - that spreads light in patterns), or refracted (D - that bends light through materials).
D
Correct answer
Explanation
On a clear day with minimal atmospheric scattering, sunlight reflected from a mirror can theoretically be visible up to about 40 km away. This depends on weather conditions, the mirror's size, and the observer's position. The curvature of Earth and atmospheric particles eventually limit visibility, but under ideal conditions, 40 km is achievable.
B
Correct answer
Explanation
Compact digital cameras do not have mirrors - they use direct sensor viewing systems. Only DSLR (Digital Single-Lens Reflex) cameras contain a mirror mechanism that reflects light up to the optical viewfinder. The mirror in a DSLR flips up when the shutter is pressed to expose the sensor. Compact cameras capture light directly onto the sensor without this reflex mirror system.
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the image is upright
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the image is located behind the mirror
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reflected rays diverge
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all of the above
D
Correct answer
Explanation
In a plane mirror, a virtual image is formed because the reflected rays diverge and appear to originate from a point behind the mirror. The image is also upright. Since all these characteristics describe the virtual image formation, 'all of the above' is correct.
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is greater than angle of reflection
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is equal to angle of reflection
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is less than angle of reflection
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changes the angle of reflection
B
Correct answer
Explanation
According to the law of reflection, the angle of incidence always equals the angle of reflection when measured from the normal (perpendicular line) to the mirror surface. This is a fundamental principle of geometric optics.
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b) and c)
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a) and c)
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All of the above ie a,b,c,d
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a) and d)
D
Correct answer
Explanation
Concave lenses always diverge light and cannot form real images. Convex mirrors also diverge light, producing only virtual images. Both concave and convex lenses can form real images depending on object position, and concave mirrors can form real images when the object is beyond the focal point.
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Inverted
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Plane
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Concave
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Convex
D
Correct answer
Explanation
Convex mirrors are used as rear-view mirrors because they provide a wider field of view by diverging reflected light rays. This allows drivers to see more area behind the vehicle, though objects appear smaller and farther away. Plane mirrors show true size but limited view, concave mirrors magnify but narrow the view, and 'inverted' is not a mirror type.
C
Correct answer
Explanation
CLARiiON arrays support a maximum of 4 bi-directional mirror relationships per array. This limitation is due to resource constraints and management complexity - each bi-directional mirror requires dedicated resources for tracking and synchronizing data in both directions. Options A and B are too low for enterprise storage needs, while option D exceeds the engineered limit.
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two
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eight
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thirty two
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infinite
D
Correct answer
Explanation
When an object is placed between two parallel mirrors, light bounces back and forth infinitely. Each reflection becomes a new object for the next reflection, creating theoretically infinite images. In practice, images become progressively dimmer due to absorption at each reflection.
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0.5 m/s
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1.0 m/s
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2.0 m/s
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3.5 m/s
B
Correct answer
Explanation
In a plane mirror, the image distance equals the object distance from the mirror surface. When you move 1 m/s toward the mirror, your image also moves 1 m/s toward you from the opposite side. The relative speed between you and your approaching image is therefore 1 m/s (not 2 m/s).
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Plane mirror
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Convex mirror
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Concave mirror
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None of these
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Concave mirror
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Convex mirror
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Plane mirror
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None of these
B
Correct answer
Explanation
Convex mirrors diverge light rays, which allows them to cover a wider field of view in a compact reflection. This property makes them ideal for rear-view mirrors and security mirrors where seeing a broad area is more important than magnification. The trade-off is that images appear smaller.
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special mirror
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plane mirror
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concave mirror
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convex mirror
C
Correct answer
Explanation
Dentists use concave mirrors because they produce magnified, virtual images when the object (teeth) is placed within the focal length of the mirror. The concave shape also converges light onto the area being examined, providing better illumination and visibility.