Which statement describes the relationship between zooming and focal length?

Which statement describes the relationship between zooming and focal length?

• A. Zooming in does not affect focal length
• B. Zooming in increases the focal length
• C. Zooming out increases the focal length
• D. Focal length changes randomly with zoom

Answer: (B)

The key idea is that a zoom lens changes its focal length as you adjust the zoom. When you zoom in, you lengthen the focal length, which increases magnification and narrows the field of view. In practical terms, going from a wider setting to a longer setting (telephoto) makes the scene appear more zoomed and closer because the lens is collecting light from a narrower angle. As you zoom out, you shorten the focal length, which broadens the field of view and reduces magnification. Focal length is an optical property of the lens itself, not how far you stand from the subject; changing distance affects framing, not the lens’s focal length. The statement that zooming in increases the focal length best captures how a zoom lens works, while the other ideas—no effect, the opposite direction, or randomness—don’t reflect how zoom mechanisms alter focal length.

The key idea is that a zoom lens changes its focal length as you adjust the zoom. When you zoom in, you lengthen the focal length, which increases magnification and narrows the field of view. In practical terms, going from a wider setting to a longer setting (telephoto) makes the scene appear more zoomed and closer because the lens is collecting light from a narrower angle.

As you zoom out, you shorten the focal length, which broadens the field of view and reduces magnification. Focal length is an optical property of the lens itself, not how far you stand from the subject; changing distance affects framing, not the lens’s focal length.

The statement that zooming in increases the focal length best captures how a zoom lens works, while the other ideas—no effect, the opposite direction, or randomness—don’t reflect how zoom mechanisms alter focal length.