Physics-
General
Easy
Question
An insect starts moving up in a liquid from point O of variable refractive index 
where y is depth of liquid from the surface. If u is the speed of insect, its apparent speed to the observer E is
- uln(1 + aH)
- none
The correct answer is:
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In the figure ABC is the cross section of a right angled prism and BCDE is the cross section of a glass slab. The value of q so that light incident normally on the face AB does not cross the face BC is 
In the figure ABC is the cross section of a right angled prism and BCDE is the cross section of a glass slab. The value of q so that light incident normally on the face AB does not cross the face BC is
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A parallel sided block of glass of refractive index 1.5 which is 36 mm thick rests on the floor of a tank which is filled with water (refractive index = 4/3). The difference between apparent depth of floor at A & B when seen from vertically above is equal to
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A ray of light is incident on a parallel slab of thickness t and refractive index n. If the angle of incidence qis small than the displacement in the incident and emergent ray will be :
A ray of light is incident on a parallel slab of thickness t and refractive index n. If the angle of incidence qis small than the displacement in the incident and emergent ray will be :
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In the figure shown 
is equal to :
In the figure shown is equal to :
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A point source of light is 60 cm from a screen and is kept at the focus of a concave mirror which reflects light on the screen. The focal length of the mirror is 20 cm. The ratio of average intensities of the illumination on the screen when the mirror is present and when the mirror is removed is :
A point source of light is 60 cm from a screen and is kept at the focus of a concave mirror which reflects light on the screen. The focal length of the mirror is 20 cm. The ratio of average intensities of the illumination on the screen when the mirror is present and when the mirror is removed is :
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In the figure shown if the object ‘O’ moves towards the plane mirror, then the image I (which is formed after successive reflections from M1 & M2 respectively) will move:
In the figure shown if the object ‘O’ moves towards the plane mirror, then the image I (which is formed after successive reflections from M1 & M2 respectively) will move:
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A concave mirror is used to form image of the Sun on a white screen. If the lower half of the mirror were covered with an opaque card, the effect on the image on the screen would be
A concave mirror is used to form image of the Sun on a white screen. If the lower half of the mirror were covered with an opaque card, the effect on the image on the screen would be
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In the figure shown, the image of a real object is formed at point I. AB is the principal axis of the mirror. The mirror must be :
In the figure shown, the image of a real object is formed at point I. AB is the principal axis of the mirror. The mirror must be :
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A ray of light is incident on a concave mirror. It is parallel to the principal axis and its height from principal axis is equal to the focal length of the mirror. The ratio of the distance of point B to the distance of the focus from the centre of curvature is (AB is the reflected ray)
A ray of light is incident on a concave mirror. It is parallel to the principal axis and its height from principal axis is equal to the focal length of the mirror. The ratio of the distance of point B to the distance of the focus from the centre of curvature is (AB is the reflected ray)
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An object O is placed in front of a small plane mirror M1 and a large convex mirror M2 of focal length f. The distance between O and M1 is x, and the distance between M1 and M2 is y. The images of O formed by M1 and M2 coincide. The magnitude of f is
An object O is placed in front of a small plane mirror M1 and a large convex mirror M2 of focal length f. The distance between O and M1 is x, and the distance between M1 and M2 is y. The images of O formed by M1 and M2 coincide. The magnitude of f is
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The circular boundary of the concave mirror subtends a cone of half angle q at its centre of curvature. The minimum value of q for which ray incident on this mirror parallel to the principle axis suffers reflection more than one is
The circular boundary of the concave mirror subtends a cone of half angle q at its centre of curvature. The minimum value of q for which ray incident on this mirror parallel to the principle axis suffers reflection more than one is
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Two mirrors AB and CD are arranged along two parallel lines. The maximum number of images of object O that can be seen by any observer is
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A point object is kept in front of a plane mirror. The plane mirror is doing SHM of amplitude 2 cm. The plane mirror moves along the x-axis and x-axis is normal to the mirror. The amplitude of the mirror is such that the object is always infront of the mirror. The amplitude of SHM of the image is
A point object is kept in front of a plane mirror. The plane mirror is doing SHM of amplitude 2 cm. The plane mirror moves along the x-axis and x-axis is normal to the mirror. The amplitude of the mirror is such that the object is always infront of the mirror. The amplitude of SHM of the image is
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In the diagram shown, all the velocities are given with respect to earth. What is the relative velocity of the image in mirror (1) with respect to the image in the mirror (2)? The mirror (1) forms an angle 
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A two eyed man is looking at the junction of two mutually perpendicular mirrors from a far off distance. Assume no reflection to occur from the edge. Then if both the eyes are open
A two eyed man is looking at the junction of two mutually perpendicular mirrors from a far off distance. Assume no reflection to occur from the edge. Then if both the eyes are open
physics-General
