Advertisements
Advertisements
प्रश्न
If an object is placed in front of a convex lens beyond 2F1, then what will be the position, relative size, and nature of an image which is formed? Explain with a ray diagram.
Advertisements
उत्तर
APPEARS IN
संबंधित प्रश्न
"A convex lens can form a magnified erect as well as magnified inverted image of an object placed in front of it." Draw ray diagram to justify this statement stating the position of the object with respect to the lens in each case.
A student has obtained a magnified image of a flame on a screen using a convex lens. To draw the corresponding ray diagram to show the image formation, which of the following two rays whose paths after refraction are shown, should he select ?
(A) I and II
(B) II and III
(C) III and IV
(D) I and III
An object is placed at a distance of 15 cm from a concave lens of focal length 30 cm. List four characteristics (nature, position, etc.) of the image formed by the lens.
A 1 cm high object is placed at a distance of 2f from a convex lens. What is the height of the image formed?
You eye contains a convex lens. Why is it unwise to look at the sun?
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
An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens.
An image formed on a screen is three times the size of the object. The object and screen are 80 cm apart when the image is sharply focussed.
State which type of lens is used.
Which causes more bending (or more refraction) of light rays passing through it : a convex lens of long focal length or a convex lens of short focal length?
In a certain murder investigation, it was important to discover whether the victim was long-sighted or short-sighted. How could a detective decide by examining his spectacles?
The given below figure shows an object OA and its image IB formed by a lens
. 
draw suitable rays to locate the lens and its focus.
To find the image distance for varying object distances in case of a convex lens of focal length 15 cm, a student obtains on a screen a sharp image of a bright object by placing it at 20 cm distance from the lens. After that he gradually moves the object away from the lens and each time focuses the image on the screen.
(a) In which direction-towards or away from the lens does he move the screen to focus the object?
(b) How does the size of image change?
(c) Approximately at what distance does he obtain the image of magnification –1?
(d) How does the intensity of image change as the object moves farther and farther away from the lens?
An object is placed perpendicular to the principal axis of a convex lens of focal length 20 cm. The distance of the object from the lens is 30 cm. Find (i) the position (ii) the magnification and (iii) the nature of the image formed.
i. Which type of microscope has the arrangement of lenses shown in the adjoining figure?
ii. Label the figure correctly.
iii. Write the working of this microscope.
iv. Where does this microscope used?
v. Suggest a way to increase the efficiency of this microscope.
A lens always forms an image between the object and the lens.
A lens always forms an image between the object and the lens.
What happens to the image formed by a convex lens if its lower part is blackened?
A beam of light is incident through the holes on side A and emerges out of the holes on the other face of the box as show in the figure. Which of the following could be inside the box?
A convex lens of focal length 20 cm can produce a magnified virtual as well as real image. Is this a correct statement? If yes, where shall the object be placed in each case for obtaining these images?
