Match the corresponding entries of column 1 with column 2. [Where m is the magnification produced by the mirror] Column 1 Column 2 (A) m = - 2 (a) Convex mirror (B) m = - 1 2 (b) Concave mirror (C) m = + 2 (c) Real image (D) m = + 1 2 (d) Virtual image

A → b and c; B → b and c; C → b and d; D → a and d

A → a and c; B → a and d; C → a and b; D → c and d

A → a and d; B → b and c; C → b and d; D → b and c

A → c and d; B → b and d; C → b and c; D → a and d

A convex mirror has a focal length f. A real object is placed at a distance of f 2 from the pole. Find out the position, magnification and nature of the image.

The mirror formula is 1 v + 1 u = 1 f , The focal length is taken positive for convex mirror. The position of the object u = - f 2 , 1 v - 2 f = 1 f ⇒ v = f 3 , The magnification is m = - v u ⇒ m = - f 3 - f 2 ⇒ m = + 2 3 , The image formed is virtual, erect and smaller than object.

EASY

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What is the magnification of convex mirror?

Important Questions on Reflection of Light

EASY

Physics>Optics>Reflection of Light>Mirror Equation

An object is placed at a distance of

20 cm

from the pole of a concave mirror of focal length

10 cm

. The distance of the image formed is

EASY

Physics>Optics>Reflection of Light>Mirror Equation

An object of height

2.5 cm

is placed perpendicularly on the principal axis of a concave mirror of focal length

f

at a distance of

\frac{3}{4} f

What will be the nature of the image of the object and its height

MEDIUM

Physics>Optics>Reflection of Light>Mirror Equation

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

f_{1}

and that of mirror is

f_{2}

. Then taking index correction to be negligibly small,

f_{1}

and

f_{2}

are close to:

HARD

Physics>Optics>Reflection of Light>Mirror Equation

A candle placed

25 cm

from a lens forms an image on the screen placed

75 cm

on the other side of the lens. The focal length and type of the lens should be

EASY

Physics>Optics>Reflection of Light>Mirror Equation

A concave mirror of focal length

15 cm

, forms an image having twice the linear dimensions of the object. The position of the object, when the image is virtual, will be

MEDIUM

Physics>Optics>Reflection of Light>Mirror Equation

A point object is moving uniformly towards the pole of a concave mirror of focal length $25 cm$ along its axis as shown below. The speed of the object is $1 {ms}^{- 1}$ . At $t = 0$ , the distance of the object from the mirror is $50 cm$ . The average velocity of the image formed by the mirror between time $t = 0$ and $t = 0.25 s$ is:

Question Image

MEDIUM

Physics>Optics>Reflection of Light>Mirror Equation

Match the corresponding entries of column 1 with column 2. [Where m is the magnification produced by the mirror]

	Column 1		Column 2
(A)	$m = - 2$	(a)	Convex mirror
(B)	$m = - \frac{1}{2}$	(b)	Concave mirror
(C)	$m = + 2$	(c)	Real image
(D)	$m = + \frac{1}{2}$	(d)	Virtual image

HARD

Physics>Optics>Reflection of Light>Mirror Equation

A magnifying glass is to be used at the fixed object distance of 1 inch. If it is to produce an erect image 5 times magnified, its focal length should be:

HARD

Physics>Optics>Reflection of Light>Mirror Equation

A convex mirror of focal length