Fascinating Facts About Focal Length and Angular Magnification
What is the relationship between focal length and angular magnification in a magnifying glass?
Given that a person with a near point at 28 cm uses a certain magnifying glass that produces an angular magnification of 7.0 with the image very distant.
What is the focal length of the lens of this magnifying glass?
Answer:
The focal length of the lens of a magnifying glass with specified angular magnification is 4 cm.
When a person with a near point at 28 cm uses a certain magnifying glass that produces an angular magnification of 7.0 with the image very distant, we can determine the focal length of the lens using the formula for angular magnification:
Angular magnification = Near point of magnifying glass / Focal length
By making the focal length the subject of the formula, we get:
Focal length = Near point of magnifying glass / Angular magnification
Substitute the values given:
Focal length = 28 cm / 7 = 4 cm
Therefore, the focal length of the magnifying glass is 4 cm. This relationship between focal length and angular magnification plays a crucial role in understanding the optics of magnifying glasses and other optical devices.