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प्रश्न
Assertion and reasoning type
- Assertion: Myopia is due to the increase in the converging power of eye lens.
- Reason: Myopia can be corrected with the help of concave lens.
पर्याय
If both assertion and reason are true and the reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
Assertion is true but reason is false.
Assertion is false but reason is true.
उत्तर
If both assertion and reason are true but reason is not the correct explanation of assertion.
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संबंधित प्रश्न
What does sign of power (+ve or –ve) indicate?
What is the nature of a lens having a power of + 0.5 D?
What is the nature of a lens whose power is, −4 D?
What do you understand by the power of a lens? Name one factor on which the power of a lens depends.
Consider three converging lenses L1, L2 and L3 having identical geometrical construction. The index of refraction of L1 and L2 are \[\mu_1 \text{ and } \mu_2\] respectively. The upper half of the lens L3 has a refractive index \[\mu_1\] and the lower half has \[\mu_2\] following figure . A point object O is imaged at O1 by the lens L1 and at O2 by the lens L2placed in same position. If L3 is placed at the same place,
(a) there will be an image at O1
(b) there will be an image at O2.
(c) the only image will form somewhere between O1 and O2
(d) the only image will form away from O2.
Surabhi from std. X uses spectacle. The power of the lenses in her spectacle is 0.5 D.
Answer the following questions from the given information:
- Identify the type of lenses used in her spectacle.
- Identify the defect of vision Surabhi is suffering from.
- Find the focal length of the lenses used in her spectacle.
Find the power of a convex lens of focal length of + 25 cm.
The power of lens depends on the focal length of the lens
A convex lens with radii of curvature R1 = R2 is immersed in water. Assuming that the refractive indices of glass and water are 3/2 and 4/3 respectively, its focal length f1 in comparison to that in air, f, is ______.
The power of convex lens of focal length 20 cm is ______.
