Advertisements
Advertisements
प्रश्न
In what unit is the power of a lens expressed?
Advertisements
उत्तर
Its unit is Dioptre (D).
APPEARS IN
संबंधित प्रश्न
What is meant by a power of a lens? Define its SI unit.
A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.
The lens mentioned in 6(b) above is of focal length 25cm. Calculate the power of the lens.
State the condition for the following a lens has both its focal lengths equal .
How does focal length of a lens change when red light incident on it is replaced by violet light? Give reason for your answer.
A convex lens produces a double size real image when an object is placed at a distance of 18 cm from it. Where should the object be placed to produce a triple size real image?
Power of a lens is – 4D, then its focal length is
The same size images are formed by a convex lens when the object is placed at 20 cm or at 10 cm from the lens. The focal length of convex lens is ______ cm.
A negative power of a lens indicates a:
The power of a lens of focal length \[f = 0.5\,m\] is:
