If the radius of curvature of a lens is 30 cm and the refractive index is 1.5, w

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Question: If the radius of curvature of a lens is 30 cm and the refractive index is 1.5, what is the focal length of the lens?

Options:

Correct Answer: 15 cm

Solution:

Using the lens maker\'s formula, f = R/(n-1) = 30/(1.5-1) = 30/0.5 = 60 cm.

If the radius of curvature of a lens is 30 cm and the refractive index is 1.5, what is the focal length of the lens?

If the radius of curvature of a lens is 30 cm and the refractive index is 1.5, what is the focal length of the lens?

Step 1: Identify the given values. The radius of curvature (R) is 30 cm and the refractive index (n) is 1.5.
Step 2: Write down the lens maker's formula: f = R / (n - 1).
Step 3: Substitute the values into the formula: f = 30 / (1.5 - 1).
Step 4: Calculate the value inside the parentheses: 1.5 - 1 = 0.5.
Step 5: Substitute this value back into the formula: f = 30 / 0.5.
Step 6: Perform the division: 30 divided by 0.5 equals 60.
Step 7: Conclude that the focal length (f) of the lens is 60 cm.

Lens Maker's Formula – The formula used to calculate the focal length of a lens based on its radius of curvature and refractive index.