Main 7 · Advanced 12
Spherical mirrors
- Main 2026PhysicsSingle correct
A rod of length 10 cm lies along the principle axis of a concave mirror of focal length 10 cm as shown in figure. The length of the image is ________ cm.
- Main 2026PhysicsInteger
A concave mirror of focal length 10 cm forms an image which is double the size of object when the object is placed at two different positions. The distance between the two positions of the object is ________ cm.
- Advanced 2025PhysicsMultiple correct
Two identical concave mirrors each of focal length are facing each other as shown in the schematic diagram. The focal length is much larger than the size of the mirrors. A glass slab of thickness and refractive index is kept equidistant from the mirrors and perpendicular to their common principal axis. A monochromatic point light source is embedded at the center of the slab on the principal axis, as shown in the schematic diagram. For the image to be formed on itself, which of the following distances between the two mirrors is/are correct:
- Advanced 2023PhysicsInteger
An optical arrangement consists of two concave mirrors and , and a convex lens L with a common principal axis, as shown in the figure. The focal length of L is 10 cm. The radii of curvature of and are 20 cm and 24 cm, respectively. The distance between L and is 20 cm. A point object S is placed at the mid-point between L and on the axis. When the distance between L and is cm, one of the images coincides with S. The value of is _____.
- Advanced 2022PhysicsInteger
An object and a concave mirror of focal length cm both move along the principal axis of the mirror with constant speeds. The object moves with speed towards the mirror with respect to a laboratory frame. The distance between the object and the mirror at a given moment is denoted by . When cm, the speed of the mirror is such that the image is instantaneously at rest with respect to the laboratory frame, and the object forms a real image. The magnitude of is _____ .
- Main 2022PhysicsInteger
An object 'o' is placed at a distance of 100 cm in front of a concave mirror of radius of curvature 200 cm as shown in the figure. The object starts moving towards the mirror at a speed 2 cm/s. The position of the image from the mirror after 10 s will be at ______ cm.
- Main 2021PhysicsSingle correct
The focal length f is related to the radius of curvature r of the spherical convex mirror by :
- Advanced 2018PhysicsMultiple correct
A wire is bent in the shape of a right angled triangle and is placed in front of a concave mirror of focal length , as shown in the figure. Which of the figures shown in the four options qualitatively represent(s) the shape of the image of the bent wire? (These figures are not to scale.)
- Advanced 2016PhysicsMultiple correct
A plano-convex lens is made of a material of refractive index . When a small object is placed 30 cm away in front of the curved surface of the lens, an image of double the size of the object is produced. Due to reflection from the convex surface of the lens, another faint image is observed at a distance of 10 cm away from the lens. Which of the following statement(s) is(are) true?
- Advanced 2016PhysicsSingle correct
A small object is placed 50 cm to the left of a thin convex lens of focal length 30 cm. A convex spherical mirror of radius of curvature 100 cm is placed to the right of the lens at a distance of 50 cm. The mirror is tilted such that the axis of the mirror is at an angle to the axis of the lens, as shown in the figure.
If the origin of the coordinate system is taken to be at the centre of the lens, the coordinates (in cm) of the point at which the image is formed are
- Main 2016PhysicsSingle correct
To find the focal length of a convex mirror, a student records the following data :
Object Pin Convex Lens Convex Mirror Image Pin 22.2 cm 32.2 cm 45.8 cm 71.2 cm The focal length of the convex lens is and that of mirror is . Then taking index correction to be negligibly small, and are close to :
- Main 2016PhysicsSingle correct
A hemispherical glass body of radius 10 cm and refractive index 1.5 is silvered on its curved surface. A small air bubble is 6 cm below the flat surface inside it along the axis. The position of the image of the air bubble made by the mirror is seen :
- Advanced 2015PhysicsInteger
Consider a concave mirror and a convex lens (refractive index = 1.5) of focal length 10 cm each, separated by a distance of 50 cm in air (refractive index = 1) as shown in the figure. An object is placed at a distance of 15 cm from the mirror. Its erect image formed by this combination has magnification . When the set-up is kept in a medium of refractive index 7/6, the magnification becomes . The magnitude is
- Main 2015PhysicsSingle correct
You are asked to design a shaving mirror assuming that a person keeps it 10 cm from his face and views the magnified image of the face at the closest comfortable distance of 25 cm. The radius of curvature of the mirror would then be :
- Advanced 2010PhysicsInteger
Image of an object approaching a convex mirror of radius of curvature 20 m along its optical axis is observed to move from m to m in 30 seconds. What is the speed of the object in km per hour?
- Advanced 2009PhysicsMultiple correct
A student performed the experiment of determination of focal length of a concave mirror by u-v method using an optical bench of length 1.5 meter. The focal length of the mirror used is 24 cm. The maximum error in the location of the image can be 0.2 cm. The 5 sets of (u, v) values recorded by the student (in cm) are: (42, 56), (48, 48), (60, 40), (66, 33), (78, 39). The data set(s) that cannot come from experiment and is (are) incorrectly recorded, is (are)
- Advanced 2008PhysicsMatrix match
An optical component and an object S placed along its optic axis are given in Column I. The distance between the object and the component can be varied. The properties of images are given in Column II. Match all the properties of images from Column II with the appropriate components given in Column I. Indicate your answer by darkening the appropriate bubbles of the 4 × 4 matrix given in the ORS.
- Advanced 2007PhysicsSingle correct
In an experiment to determine the focal length of a concave mirror by the - method, a student places the object pin A on the principal axis at a distance from the pole P. The student looks at the pin and its inverted image from a distance keeping his/her eye in line with PA. When the student shifts his/her eye towards left, the image appears to the right of the object pin. Then,
- Advanced 2007PhysicsAssertion and reason
STATEMENT-1: The formula connecting , and for a spherical mirror is valid only for mirrors whose sizes are very small compared to their radii of curvature.
because
STATEMENT-2: Laws of reflection are strictly valid for plane surfaces, but not for large spherical surfaces.