Lens-Maker's Formula: a Compound Lens Is Made by Joining the Plane

question 91

Multiple Choice

Lens-maker's formula: A compound lens is made by joining the plane surfaces of two thin plano-convex lenses of different glasses. The radius of curvature of each convex surface is 80 cm. The indices of refraction of the two glasses are 1.50 and 1.60. What is the focal length of the compound lens?

• A) 67 cm
• B) 69 cm
• C) 71 cm
• D) 73 cm
• E) 75cm

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Definitions:

Experimental Group

In research, the group of participants that receives the treatment or intervention being tested, contrasted with the control group.

Independent Variable

The variable that is intentionally changed or manipulated in an experiment to observe its effect on the dependent variable.

Dependent Variable

In experimental and statistical research, the variable being tested and measured, subject to change under the influence of the independent variable.

Hypothesis

A proposed explanation for a phenomenon, made as a starting point for further investigation.