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प्रश्न
A candle is placed between f and 2f a convex lens. Draw a ray diagram showing the position of the image.
उत्तर
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संबंधित प्रश्न
To determine the approximate focal length of the given convex lens by focussing a distant object (say, a sign board), you try to focus the image of the object on a screen. The image you obtain on the screen is always
(a) erect and laterally inverted
(b) erect and diminished
(c) inverted and diminished
(d) virtual, inverted and diminished
The diagram given alongside shows a ray of light entering a rectangular block of glass.
(a) Copy the diagram and draw the normal at the point of entry.
(b) Draw the approximate path of the ray of light through the glass block and out of the other side.
Draw a labelled ray diagram to show how a ray of light passes through a parallel sided glass block:
if it hits the glass block at 90° (that is, perpendicular to the glass block)
f the image formed by a convex lens is of the same size as that of the object, what is the position of the image with respect to the lens?
State any two uses of convex lenses.
With the help of a labelled diagram explain how a convex lens converges a beam of parallel light rays. Mark the principal axis, optical centre, principal focus and focal length of the convex lens on the diagram.
Find the nature, position and magnification of the images formed by a convex lens of focal length 0.20 m if the object is placed at a distance of:
0.50 m
A student did an experiment with a convex lens. He put an object at different distances 25 cm, 30 cm, 40 cm, 60 cm and 120 cm from the lens. In each case he measured the distance of the image from the lens. His results were 100 cm, 24 cm, 60 cm, 30 cm and 40 cm, respectively. Unfortunately his results are written in wrong order.
What is the focal length of this lens?
Study the diagram given below.
- Name the lens LL’.
- What are the points O and O’ called?
- Complete the diagram to form the image of the object AB.
- State the three characteristics of the image.
- Name a device in which this action of lens is used.
Can a normal convex lens behave like a concave lens and vice-versa?
