Advertisements
Advertisements
प्रश्न
Which type of lens has a positive power?
Advertisements
उत्तर
A convex lens has positive power.
APPEARS IN
संबंधित प्रश्न
Calculate the focal length of a corrective lens having power +2.5 D.
Which of the two has a greater power: a lens of short focal length or a lens of large focal length?
The focal length of a convex lens is 25 cm. What is its power?
The power of a lens is + 0.2 D. Calculate its focal length.
An object of height 4.25 mm is placed at a distance of 10 cm from a convex lens of power +5D. Find (i) the focal length of the lens, and (ii) the size of the image.
The power of a combination of two lenses X and Y is 5 D. If the focal length of lens X be 15 cm :
(a) calculate the focal length of lens Y.
(b) state the nature of lens Y.
Name the type of lens whose power is positive.
The image of an object formed by a lens is real, inverted and of the same size as the object. If the image is at a distance of 40 cm from the lens, what is the nature and power of the lens ? Draw ray diagram to justify your answer.
A normal eye is not able to see objects closer than 25 cm because
A double convex lens has two surfaces of equal radii R and refractive index \[m = 1 \cdot 5\]
A 5.0 diopter lens forms a virtual image which is 4 times the object placed perpendicularly on the principal axis of the lens. Find the distance of the object from the lens.
Which lens has more power a thick lens or a thin lens?
Find the power of a convex lens of focal length of + 25 cm.
Increase in the converging power of eye lens cause ‘hypermetropia'
In what unit is the power of a lens expressed?
The deviation of the incident light rays produced by a lens on refraction through it is a measure of its:
The power of a lens is defined as the:
A negative power of a lens indicates a:
If the lens material and the surrounding liquid have the same refractive index (\[n_2 = n_1\]), then:
A convex lens has:
A lens has a power of \[+2\,D\]. Its focal length is:
