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:

Virtual Memory

A method of simulating extra memory by using the hard disk space as if it were RAM.

Motherboard RAM

Refers to the Random Access Memory slots situated on the motherboard where memory modules are inserted to provide the system's working memory.

SPD Device

Surge Protection Device, a device designed to protect electrical equipment from voltage spikes by blocking or shorting to ground undesired voltages.

TPM Module

Trusted Platform Module, a specialized chip on an endpoint device that stores RSA encryption keys specific to the host system for hardware authentication.