JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
The graph shows how the magnification \(m\) produced by a thin lens varies with image distance \(v\). What is the focal length of the lens used?
- A \(\frac {b^2}{ac}\)
- B \(\frac {a}{c}\)
- C \(\frac {b^2c}{a}\)
- D \(\frac {b}{c}\)
Answer & Solution
Correct Answer
(D) \(\frac {b}{c}\)
Step-by-step Solution
Detailed explanation
\(f\,=\,\frac {b}{c}\)
See the Complete Solution
Get step-by-step explanations for this and 2.5 Lakh+ more JEE, NEET & CET questions.
- Unlock all solutions
- Practice the full chapter
- Track accuracy across PYQs
4.8 rated on Google Play · 14,000+ reviews
More questions from Physics
- Figure shows the circuit that contains three resistances (9 Ω each) and two inductors (4 mH each). The reading of ammeter at the moment switch K is turned ON, is__________ A.
JEE Mains 2026 Medium - Two masses 400 g and 350 g are suspended from the ends of a light string passing over a heavy pulley of radius 2 cm . When released from rest the heavier mass is observed to fall 81 cm in 9 s . The rotational inertia of the pulley is _________ \(kg \cdot m ^2\).\(\left( g =9.8 m / s ^2\right)\)JEE Mains 2026 Hard
- The net current flowing in the given circuit is_______ A.
JEE Mains 2025 Medium - The wavelength of an \(X-\)ray beam is \(10 \, \mathring A\). The mass of a fictitious particle having the same energy as that of the \(X-\)ray photons is \(\frac{ x }{3} h \,kg\). The value of \(x\) is ....... . \((h =\) Planck's constant \()\)JEE Mains 2021 Medium
- XPQY is a vertical smooth long loop having a total resistance R where PX is parallel to QY and separation between them is \(l\). A constant magnetic field B perpendicular to the plane of the loop exists in the entire space. A rod CD of length L (L > \(l\)) and mass m is made to slide down from rest under the gravity as shown in figure. The terminal speed acquired by the rod is __________ m/s.
(g = acceleration due to gravity)
JEE Mains 2026 Easy - During the melting of a slab of ice at 273 K at atmospheric pressure :JEE Mains 2025 Easy
More PYQs from JEE Mains
- The equation of a tangent to the hyperbola \(4x^2 -5y^2 = 20\) parallel to the line \(x -y = 2\) isJEE Mains 2019 Hard
- Four persons can hit a target correctly with probabilities \(\frac{1}{2},\frac{1}{3},\frac{1}{4}\) and \(\frac {1}{8}\) respectively. If all hit at the target independently, then the probability that the target would be hit, isJEE Mains 2019 Hard
- An urn contains \(6\) white and \(9\) black balls. Two successive draws of \(4\) balls are made without replacement. The probability, that the first draw gives all white balls and the second draw gives all black balls, is :JEE Mains 2024 Medium
- Let the Mean and Variance of five observations \(x_1=1, x_2=3, x_3=a, x_4=7\) and \(x_5=b, a \gt b\), be 5 and 10 respectively. Then the Variance of the observations \(n+x_n, n=1,2, \ldots \ldots . .5\) isJEE Mains 2025 Medium
- The graph shows variation of stopping potential \(V_o\) with the frequency \(\nu\) of the incident radiation for three photosensitive metals \(X_1\), \(X_2\) and \(X_3\). Which metal will give out electrons with greater kinetic energy, for the same wavelength of incident radiation?
JEE Mains 2026 Medium - A child of mass \(5\,kg\) is going round a merry-goround that makes \(1\) rotation in \(3.14\,s\). The radius of the merry-go-round is \(2\,m\). The centrifugal force on the child will be \(.......\,N\)JEE Mains 2023 Medium