EASY
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What is lateral inversion?

Important Questions on Light

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
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 girl is standing 7 m from a plane mirror. The distance of the girl from her image in the mirror is
EASY
 Which mirror has an infinite focal length? 
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?
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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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

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
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
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 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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EASY
What is reflection? Write the laws of reflection.
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A ray deviates at 90° after suffering reflection from a mirror. The angle of incidence is
EASY
Which of the following statements is true?
HARD

A light ray is incident, at an incident angle θ1, on the system of two plane mirrors M1 and M2 having an inclination angle 75° between them (as shown in figure). After reflecting from mirror M1 it gets reflected back by the mirror M2 with an angle of reflection 30°. The total deviation of the ray will be _____ degree.

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MEDIUM

The figure shows two plane mirrors inclined at 50°. A ray is incident on one of the mirrors at an arbitrary angle α. It gets reflected from this mirror and then from the other mirror.

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The angle between the incident ray and the emergent ray 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)?
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?
EASY
Focal length, radius of curvature and power of a plane mirror respectively are