EASY
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What do you mean by lateral inversion?

Important Questions on Light

HARD

The image of an object O due to reflection from the surface of a lake is elongated due to the ripples on the water surface caused by a light breeze. This is because the ripples act as tilted mirrors as shown below. Consider the case, where O and the observer E are at the same height above the surface of the lake. If the maximum angle that the ripples make with the horizontal is α, then the angular extent δ of the image will be

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EASY
A beam of light from a source L is incident normally on a plane mirror fixed at a certain distance x from the source. The beam is reflected back as a spot on a scale placed just above the source L. When the mirror is rotated through a small angle θ, the spot of the light is found to move through a distance y on the scale. The angle θ is given by
MEDIUM

Letters A,B,C and D are written on a cardboard as shown in the figure below.

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The cardboard is kept at a suitable distance behind a transparent empty glass of cylindrical shape. If the glass is now filled with water, one sees an inverted image of the pattern on the cardboard when looking through the glass. Ignoring magnification effects, the image would appear as

EASY
A ray deviates at 90° after suffering reflection from a mirror. The angle of incidence is
MEDIUM

A point source of light, S is placed at a distance L in front of the center of plane mirror of width d which is hanging vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror, at a distance 2L as shown below. The distance over which the man can see the image of the light source in the mirror is:

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MEDIUM
A man is 160 cm tall and his eyes are 15 cm below the top of his head. In order to see his entire height, right from the top to head, he uses a plane mirror kept at a distance of 1 m from him. The minimum length of the plane mirror required is
HARD
A point source is placed at coordinates (0,1) in xy -plane. A ray of light from the source is reflected on a plane mirror placed along the X -axis and perpendicular to the xy -plane. The reflected ray passes through the point (3,3) . What is the path length of the ray from (0,1) to (3,3)?
EASY
What is reflection? Write the laws of reflection.
MEDIUM
A flat mirror revolves at a constant angular velocity making n=0.4 revolutions per second. With what velocity (in m s-1) will a light spot move along a spherical screen with a radius of 15 m, if the mirror is at the centre of curvature of the screen?
HARD
A ray of light, travelling in the direction 12i^+3 j^, is incident on a plane mirror. After reflection, it travels along the direction 12i^-3 j^. The angle of incidence is
EASY
What is the minimum size of mirror required for a 6ft tall person to be able to see a full length image?
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Distinguish between real image and virtual image. (Mention any two points.)

EASY
 Which mirror has an infinite focal length? 
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A girl is standing 7 m from a plane mirror. The distance of the girl from her image in the mirror is
MEDIUM
A tank is filled with water to a height of 12.5 cm. The apparent depth of a needle lying at the bottom of the tank is measured by a microscope to be 9.4 cm. What is the refractive index of water?
MEDIUM
A man of height H stands at a distance D from a mirror fixed on the wall. His eye level is at the same height as the top edge of the mirror. What must be the minimum length L of the mirror so that he can see his entire body in the mirror? You can assume that the eye-level is the same as the top of his head.
EASY
Which of the following statements is true?
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A mirror is placed at an angled of 30° with respect to y-axis (see figure). A light ray travelling in the negative y-direction strikes the mirror. The direction of the reflected ray is given by the vector

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EASY
Focal length, radius of curvature and power of a plane mirror respectively are
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Distinguish between real image and virtual image.