| ⇦ |
| ⇨ |
A person wants a real image of his own, 3 times enlarged. Where should he stand in front of a concave mirror of radius of curvature of 30 cm?
Options
(a) 90 cm
(b) 10 cm
(c) 20 cm
(d) 30 cm
Correct Answer:
20 cm
Explanation:
Given, m = -3 and R = 30 cm
f = -(R / 2) = -15 cm
We know that, m = -(v / u) ⇒ -3 = -v / u
Therefore, v= 3u
1/f = (1/v) + (1/u) ⇒ (1/-15) = (1/3u) + (1/u) = (1+3) / 3u
-3u = 4 × 15
u = (-4 × 15) / 3
Initial position of a person, u = -20 cm
Related Questions: - IF A⃗ and B⃗ are two vectors and θ is the angle between them
- In the diagram shown in figure, match the following about weight
- Which of the following statements is correct?
- A series L-C-R circuit contains inductance 5 mH, capacitance 2 μF and resistance
- A bar magnet having a magnetic moment of 2 x 10⁴JT⁻¹ is free to rotate in a horizontal
Topics: Ray Optics
(94)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- IF A⃗ and B⃗ are two vectors and θ is the angle between them
- In the diagram shown in figure, match the following about weight
- Which of the following statements is correct?
- A series L-C-R circuit contains inductance 5 mH, capacitance 2 μF and resistance
- A bar magnet having a magnetic moment of 2 x 10⁴JT⁻¹ is free to rotate in a horizontal
Topics: Ray Optics (94)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends

Leave a Reply