A biconvex lens has a radius of curvature of 30 cm on both sides. What is the fo

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Question: A biconvex lens has a radius of curvature of 30 cm on both sides. What is the focal length of the lens if the refractive index is 1.5?

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.

A biconvex lens has a radius of curvature of 30 cm on both sides. What is the focal length of the lens if the refractive index is 1.5?

A biconvex lens has a radius of curvature of 30 cm on both sides. What is the focal length of the lens if the refractive index is 1.5?

Step 1: Identify the radius of curvature (R) of the lens. In this case, R = 30 cm.
Step 2: Identify the refractive index (n) of the lens material. Here, n = 1.5.
Step 3: Use the lens maker's formula for a biconvex lens: f = R / (n - 1).
Step 4: Substitute the values into the formula: f = 30 / (1.5 - 1).
Step 5: Calculate the denominator: 1.5 - 1 = 0.5.
Step 6: Now substitute this value back into the formula: f = 30 / 0.5.
Step 7: Perform the division: 30 divided by 0.5 equals 60.
Step 8: Therefore, 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.
Refractive Index – A measure of how much light bends when entering a material, affecting the lens's focal length.
Radius of Curvature – The distance from the lens's surface to its center of curvature, influencing the lens's optical properties.