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प्रश्न
According to cartesion sign convention, which mirror and which lens has negative focal length?
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उत्तर
Concave mirror is having a negative focal length.
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संबंधित प्रश्न
To determine the approximate value of the focal length of a given concave mirror, you focus the image of a distant object formed by the mirror on a screen. The image obtained on the serene, as compared to the object is always:
(a) Laterally inverted and diminished
(b) Inverted and diminished
(c) Erect and diminished
(d) Erect and highly diminished
A spherical mirror produces an image of magnification −1 on a screen placed at a distance of 40 cm from the mirror:
(i) Write the type of mirror.
(ii) What is the nature of the image formed?
(iii) How far is the object located from the mirror?
(iv) Draw the ray diagram to show the image formation in this case.
Name the mirror that can give an erect and enlarged image of an object.
Three students A, B and C focussed a distant building on a screen with the help of a concave mirror. To determine focal length of the concave mirror they measured the distances as given below:
Student A : From mirror to the screen
Student B : From building to the screen
Student C : From building to the mirror
Who measured the focal length correctly ;
(a) Only A
(b) Only B
(c) A and B
(d) B and C
At what distance from a concave mirror focal length 10 cm should an object 2 cm long be placed in order to get an erect image 6 cm tall?
An object is 24 cm away from a concave mirror and its image is 16 cm from the mirror. Find the focal length and radius of curvature of the mirror, and the magnification of the image.
A student obtained a sharp inverted image of a distant tree on a screen placed in front of the concave mirror. He then removed the screen and tried to look into the mirror. He would now see
(A) a very blurred image on the wall opposite to the mirror
(B) an erect and magnified image of the tree in the mirror
(C) no image as the screen has been removed
(D) a highly diminished inverted image of the tree at the focus of the mirror.
Large ______ mirrors are used to concentrate sunlight to produce heat in solar furnaces.
Beams of light are incident through the holes A and B and emerge out of box through the holes C and D respectively as shown in the figure. Which of the following could be inside the box?
Between which two points of a concave mirror should an object be placed to obtain a magnification of -2?
