Return to Blog
Homepage
MCAT Physics Question — Converging Lens
- by
- Mar 05, 2017
- MCAT Question of the Day
The combination of the cornea and the crystalline lens shown below serves as a converging lens. In a perfectly functioning eye, an image is projected at a fixed distance on the retina, which is approximately 2cm from the lens. What is the power of the converging lens when a person without any visual impairment stares at a distant object?
- 0.5 diopters
- 10 diopters
- 25 diopters
- 50 diopters
Click for Explanation
To answer this question, you must use the thin lens equation 1/f = 1/do + 1/di, where f is the focal length, do is the object distance, and di is the image distance. Since the power (P) of a lens is equal to 1/f, you can set P = 1/do + 1/di.
The question stem states that image distance is fixed and equal to a length of 2 cm. Since the question states that the observer stares at a distant object, we can assume that 1/do is negligible and equal to zero. Therefore, the equation simplifies to P = 1/di. Since power is measured in diopters, which has the units of m-1, you must convert 2 cm to 0.02 m and solve. Thus, the power of the lens is equal to 50 diopters, or answer choice D.
Want more MCAT practice?
We’ve got options for every schedule and learning style!
From the best online MCAT course created by top instructors with 524+ MCAT scores to the most representative full-length practice exams and private tutoring, we can custom tailor your MCAT prep to your goals!
Not sure which option is right for you? Schedule a free MCAT consultation with an MCAT expert using the form below. No obligation, just expert advice.
Related Post
Search the Blog
Free Consultation
Interested in our Online MCAT Course or one of our One-on-One MCAT Tutoring packages? Set up a free consultation with one of our experienced Academic Managers!
Schedule NowPopular Posts
-
MCAT Blog How To Prep For The MCAT During COVID-19 -
-
-
MCAT Blog How is the MCAT Scored? -
MCAT Blog Should You Retake the MCAT? -
-
Free MCAT Practice Account
Need great MCAT practice?Get the most representative MCAT practice possible when you sign up for our free MCAT Account, which includes a half-length diagnostic exam and one of our full-length MCAT practice exams.
Learn More
Submit a Comment