The Focal Length of the Lens of a Simple Camera

question 28

Multiple Choice

The focal length of the lens of a simple camera is 40.0 mm. How far must the lens be moved to change the focus of the camera from a person 25 m away to one that is 4.0 m away?

• A) 0.2 mm
• B) 0.3 mm
• C) 0.4 mm
• D) 0.5 mm
• E) 0.7 mm

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Definitions:

Varicella

Also known as chickenpox is a highly contagious disease caused by the varicella-zoster virus.

Chicken Pox

A highly contagious viral infection causing an itchy rash and red spots or blisters (varicella).

Contagious Disease

An illness that can be transmitted from one individual to another through direct or indirect contact.

Z-track IM

A method of intramuscular injection designed to seal the medication in the muscle tissue, preventing leakage into the subcutaneous tissue.