A Drawing Is Placed $40 \mathrm {~cm}$ In Front of a Thin Lens

question 79

Multiple Choice

A drawing is placed $40 \mathrm {~cm}$ in front of a thin lens. If a virtual image forms at a distance of $50 \mathrm {~cm}$ from the lens, on the same side as the drawing, what is the focal length of the lens?

• A) \(- 45 \mathrm {~cm}\)
• B) \(+ 45 \mathrm {~cm}\)
• C) \(75 \mathrm {~cm}\)
• D) \(90 \mathrm {~cm}\)
• E) \(200 \mathrm {~cm}\)

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Definitions:

Motor Control Center

A centralized assembly of electric motor controls, circuit protectors, and distribution panels that manage the operation of multiple electric motors.

Electric Motor Starters

Devices used to control the initial surge of current when an electric motor is started, protecting the motor from damage due to high currents.

Commercial

Pertaining to business activities, transactions, or establishments primarily focused on profitability.

Necessary Control

Essential mechanisms or systems required to regulate the operation of machines, processes, or systems to achieve desired outcomes.