A Cell Phone That Is $8.90 \mathrm {~cm}$ Tall Is Placed in Front of a Convex Mirror

question 90

Multiple Choice

A cell phone that is $8.90 \mathrm {~cm}$ tall is placed in front of a convex mirror. The image of the phone is $7.80 \mathrm {~cm}$ tall and is located $14.8 \mathrm {~cm}$ from a mirror. What is the mirror's focal length?

• A) \(+ 120 \mathrm {~cm}\)
• B) \(- 105 \mathrm {~cm}\)
• C) \(- 120 \mathrm {~cm}\)
• D) \(+ 16.9 \mathrm {~cm}\)
• E) \(- 13.0 \mathrm {~cm}\)

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Definitions:

Elliptical Orbit

The path taken by an object in space that revolves around another object in an ellipse shape, typical of planets and comets in our solar system.

Kepler

A German mathematician and astronomer known for his laws of planetary motion, which provided one of the foundations for Isaac Newton's theory of universal gravitation.

Scientific Experimentation

The systematic investigation of scientific theories and hypotheses through controlled and observable experiments.