The focal length of a plane mirror is (1) Positive (2) Negative (3) Zero (4) Infinity

1 Answer

Answer :

(4) Infinity Explanation: A plane mirror is a mirror with a flat reflective surface. The focal length of a plane mirror is infinity. Its optical power is zero.

Related questions

Description : An object is placed at a distance equal to the focal length of convex mirror. If the focal length of the mirror be f, then the distance of the image from the pole of the mirror is (a) Less than f (b) Equal of f (c) More than f (d) Infinity

Last Answer : Ans:(a)

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Description : The focal length of a concave mirror is 2 meters. An object is positioned 8 meters in front of the mirror. Is the image of this object real or virtual? 

Last Answer : ANSWER: REAL

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Last Answer : ANSWER: 2 METERS

Description : The focal length of a concave mirror is 2 meters. An object is positioned 8 meters in front of the mirror. Where is the image of this object formed?

Last Answer : ANSWER: 8/3 METER or 2.66 METERS IN FRONT OF THE MIRROR

Description : The power of a lens (A) Is reciprocal of its focal length (B) Is positive if it is a convex lens (C) Is negative if it is a concave lens (D) Is measured in Diopter

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Description : 14. An object 2 cm in size is placed 30 cm in front of a concave mirror of focal length 15 cm. At what distance from the mirror should a screen be placed in order to obtain a sharp image? What will be the nature and the size of the -Chemistry-10

Last Answer : Answer. hope this helps you

Description : 15. An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed so that a sharply focused image can be obtained? Find the size and nature of the image. -Physics-10

Last Answer : Object distance (u) = – 27 cm Object height (h) = 7 cm Focal length (f) = – 18 cm According to the mirror formula, The negative value of image height indicates that the image formed is inverted.

Description : 12. An object is placed at a distance of 10 cm from a convex mirror of focal length 15 cm. Find the position and nature of the image. -Physics-10

Last Answer : Focal length of convex mirror (f) = +15 cm Object distance (u) = - 10 cm According to the mirror formula, The image is located at a distance of 6 cm from the mirror on the other ... and a value of less than 1 of magnification indicates that the image formed is virtual and erect and diminished.

Description : We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? -Physics-10

Last Answer : Range of the distance of the object = 0 to 15 cm from the pole of the mirror. Nature of the image = virtual, erect, and larger than the object.

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Description : 1. Find the focal length of a convex mirror whose radius of curvature is 32 cm. -Physics-10

Last Answer : Radius of curvature (R) = 32 cm Radius of curvature = 2 × Focal length (f) R= 2f f = R/2 = 32/2 = 16 Therefore, the focal length of the given convex mirror is 16 cm.

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Last Answer : Radius of curvature (R) = 20 cm Radius of curvature of the spherical mirror = 2 × Focal length (f) R = 2f f= R/2 = 20 / 2 = 10 Therefore, the focal length of the spherical mirror is 10 cm.

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Last Answer : For magnified and erect image the object is placed between pole P and focus F. For magnified and inverted image the object is placed either at focus or anywhere between F and C.

Description : The focal length of a concave mirror is 10 cm and the distance from the mirror to the object is 5 cm . If so, what will be the reflection ?

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Description : A concave lens focal length 10 cm is placed on the axis of concave mirror of 10 cm radius at a distance of 5 cm from the mirror. An object is placed s

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Description : An object of height 4 cm is kept at a distance of 80 cm from the pole af a diverging mirror. If the focal length of the mirror is 10 cm. the height of the image formed is (a) + 3.0 cm (b) + 2.5 cm (c) + 1.0 cm (d) + 0.75 cm

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Description : The focal length of mirror is (a) -16 cm (b) 12 cm (c) -15 cm (d) 10 cm

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Description : If the radius of curvature of concave mirror is 12 cm. Then, the focal length will be : (a) 12 cm (b) 6 cm (c) -24 cm (d) -6 cm

Last Answer : (b) 6 cm

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