MEDIUM
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It is necessary to illuminate the bottom of a well by reflected solar beam when the light is incident at an angle of α=40° to the vertical. At what angle β to the horizontal should a plane mirror be placed?

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Important Questions on Ray Optics

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 ray deviates at 90° after suffering reflection from a mirror. The angle of incidence is
MEDIUM
Two plane mirrors M1 and M2 are at right angle to each other shown. A point source P is placed at a and 2a meter away from M1 and M2 respectively. The shortest distance between the images thus formed is : (Take 5=2.3)
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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
Focal length, radius of curvature and power of a plane mirror respectively are
EASY
Two plane mirrors are inclined to each other at an angle of 60°. A point object is placed in between them. The total number of images produced by both the mirrors is
EASY
What is the minimum size of mirror required for a 6ft tall person to be able to see a full length image?
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
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 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.
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?
MEDIUM

A point source of light S, placed at a distance 60 cm infront of the centre of a plane mirror of width 50 cm, hangs vertically on a wall. A man walks infront of the mirror along a line parallel to the mirror at a distance 1.2 m from it (see in the figure). The distance between the extreme points where he can see the image of the light source in the mirror is__cm

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EASY
A girl is standing 7 m from a plane mirror. The distance of the girl from her image in the mirror is
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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HARD

Three plane mirrors form an equilateral triangle with each side of length L. There is a small hole at a distance l>0 from one of the corners as shown in the figure. A ray of light is passed through the hole at an angle θ and can only come out through the same hole. The cross section of the mirror configuration and the ray of light lie on the same plane.

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Which of the following statement(s) is(are) correct?

EASY

Image formed by a plane mirror is erect, virtual and _____.

HARD

Two plane mirrors are kept on a horizontal table making an angle θ with each other as shown schematically in the figure. The angle θ is such that any ray of light reflected after striking both the mirrors return parallel to its incident path. For this to happen, the value of θ should be

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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
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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