When a Person Stands 40 Cm in Front of a Cosmetic

question 147

Multiple Choice

When a person stands 40 cm in front of a cosmetic (concave) spherical mirror, the upright image is twice the size of the object. What is the focal length of the mirror?

• A) 80 cm
• B) 40 cm
• C) 27 cm
• D) 160 cm

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Definitions:

Atomic Sentences

The most basic form of sentences in logic that do not include logical connectives and convey a full idea.

Truth Values

In logic, the valuation of a statement as either true or false.

Truth Table

A mathematical table used in logic to compute the truth values of logical expressions based on their variables' truth values.

Atomic Sentences

The most basic elements of logical statements, neither composed of, nor divisible into, simpler statements.