PHYSICS

JAMB 2011 - Question 27

Physics 2011 JAMB Past Questions - Question 27: A certain far-sighted person cannot see objects closer to the eyes than 50 cm clearly.Determine the power of the converging lens which will enable him to see at 25cm

Choose the correct answers from the options given.
A certain far-sighted person cannot see objects closer to the eyes than 50 cm clearly.Determine the power of the converging lens which will enable him to see at 25cm
A:
B:
C:
D:
Examkits App

Examkit's JAMB CBT App

Practice JAMB offline with our Online, PC and Mobile App

  • ✅ 25+ years of past questions (2000 to 2025)
  • ✅ Video solutions and explanation to questions
  • ✅ E-library
  • ✅ Study by topic
  • ✅ And more.

Correct Answer

B

Explanation

To determine the power of a converging lens that will enable a person to see objects at a closer distance, you can use the lens formula:

\[P = \frac{1}{f}\]

Where:
- P is the power of the lens in diopters (D).
- f is the focal length of the lens in meters (m).

In this case, the person cannot see objects closer to the eyes than 50 cm clearly, and they want to be able to see objects at 25 cm. The focal length of the lens needed to achieve this can be calculated as follows:

\[f = \frac{1}{d}\]

Where:
- d is the desired object distance, which is 25 cm (0.25 m).

Now, let's calculate the focal length of the lens:

\[f = \frac{1}{0.25 \, \text{m}} = 4 \, \text{m}^{-1}\]

Now that you have the focal length, you can calculate the power of the lens using the lens formula:

\[P = \frac{1}{f} = \frac{1}{4 \, \text{m}^{-1}} = 4 \, \text{D}\]

So, the power of the converging lens that will enable the person to see objects at 25 cm is 4 diopters.

Frequently Asked Questions

Examkits is a JAMB CBT practice platform that provides over 20 years of past questions, Post UTME questions, and detailed video solutions to help students prepare for their exams.

You can practice JAMB past questions online, on Android, or on a desktop using the Examkits app. Just register on our website and choose your preferred device.

Yes. Our Android and Windows versions support offline usage. Once downloaded and activated, no internet is required to use most of the features.

Yes, Examkits provides detailed video explanations for all JAMB past questions from 2000 to 2024, helping students understand how to solve each problem.

Examkits offers free practice for some subjects. However, full access requires a one-time affordable activation fee for each version of the app.