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Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .?
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Calculate both power and focal length of a concave lens whose radii of...
Calculation of Power and Focal Length of a Concave Lens
Given:
- Radii of curvature (R) = -20 cm (negative sign indicates a concave lens)
- Refractive index (n) of the lens = 1.5
Formula:
The power (P) of a lens is given by the formula:
P = (n - 1) * (1 / R)
The focal length (f) of a lens can be calculated using the formula:
f = 1 / P
Calculation of Power:
Substituting the given values into the formula, we have:
P = (1.5 - 1) * (1 / -20)
P = 0.5 * (-1/20)
P = -0.025 D
Therefore, the power of the concave lens is -0.025 D (negative sign indicates a diverging lens).
Calculation of Focal Length:
Using the formula for focal length, we have:
f = 1 / (-0.025)
f = -40 cm
Therefore, the focal length of the concave lens is -40 cm, which also indicates a diverging lens.
Explanation:
- The power of a lens is a measure of its ability to converge or diverge light rays. A positive power indicates a converging lens, while a negative power indicates a diverging lens.
- The formula for the power of a lens involves the refractive index of the lens and the radii of curvature of its surfaces.
- In this case, the radii of curvature of the concave lens are given as 20 cm each. Since the radii are negative, it indicates that the lens is concave or diverging.
- The refractive index of the lens is given as 1.5, which represents the ratio of the speed of light in vacuum to the speed of light in the lens material.
- By substituting the values into the power formula, we can calculate the power of the lens.
- The focal length of a lens is the distance between the lens and the point where parallel rays of light converge or appear to diverge.
- The focal length can be calculated using the formula f = 1 / P, where P is the power of the lens.
- By substituting the calculated power value into the focal length formula, we can determine the focal length of the concave lens.
- The negative values for both power and focal length indicate that the concave lens is diverging, meaning it causes parallel rays of light to spread out or appear to originate from a virtual point.
Given:
- Radii of curvature (R) = -20 cm (negative sign indicates a concave lens)
- Refractive index (n) of the lens = 1.5
Formula:
The power (P) of a lens is given by the formula:
P = (n - 1) * (1 / R)
The focal length (f) of a lens can be calculated using the formula:
f = 1 / P
Calculation of Power:
Substituting the given values into the formula, we have:
P = (1.5 - 1) * (1 / -20)
P = 0.5 * (-1/20)
P = -0.025 D
Therefore, the power of the concave lens is -0.025 D (negative sign indicates a diverging lens).
Calculation of Focal Length:
Using the formula for focal length, we have:
f = 1 / (-0.025)
f = -40 cm
Therefore, the focal length of the concave lens is -40 cm, which also indicates a diverging lens.
Explanation:
- The power of a lens is a measure of its ability to converge or diverge light rays. A positive power indicates a converging lens, while a negative power indicates a diverging lens.
- The formula for the power of a lens involves the refractive index of the lens and the radii of curvature of its surfaces.
- In this case, the radii of curvature of the concave lens are given as 20 cm each. Since the radii are negative, it indicates that the lens is concave or diverging.
- The refractive index of the lens is given as 1.5, which represents the ratio of the speed of light in vacuum to the speed of light in the lens material.
- By substituting the values into the power formula, we can calculate the power of the lens.
- The focal length of a lens is the distance between the lens and the point where parallel rays of light converge or appear to diverge.
- The focal length can be calculated using the formula f = 1 / P, where P is the power of the lens.
- By substituting the calculated power value into the focal length formula, we can determine the focal length of the concave lens.
- The negative values for both power and focal length indicate that the concave lens is diverging, meaning it causes parallel rays of light to spread out or appear to originate from a virtual point.
Community Answer
Calculate both power and focal length of a concave lens whose radii of...
5 and 20
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Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .?
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Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .?.
Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Calculate both power and focal length of a concave lens whose radii of curvature is 20cm each at refractive index of the lens is 1.5 .?.
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