JEE Mains · Physics · STD 12 - Ray optics and optical instruments
- JEE Mains 2024
- Hard
- MCQ
The position of the image formed by the combination of lenses is _______. \(\mathrm{f}_1=10 \mathrm{~cm} \quad \mathrm{f}_2=10 \quad \mathrm{f}_3=30 \mathrm{~cm}\)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(30 \mathrm{~cm}\) (right of third lens)
Step-by-step Solution
Detailed explanation
For lens \(1: f_1=10, u=-30, v=\) ?
\(v=\frac{u f}{u+f}=\frac{-30 \times 10}{-30+10}=15\)
For lens 2: \(f_1=-10, u=10, v=\) ?
\(\mathrm{v}=\frac{\mathrm{uf}}{\mathrm{u}+\mathrm{f}}=\frac{10 \times-10}{10-10}=\infty\)
For lens \(3: f=30, u=-\infty, v=\) ?
So v will be \(30\).
More questions from Physics
- \(27\) identical drops are charged at \(22\, V\,\,each.\) They combine to form a bigger drop. The potential of the bigger drop will be............ \(V.\)JEE Mains 2022 Medium
- A magnet hung at \(45^{\circ}\) with magnetic meridian makes an angle of \(60^{\circ}\) with the horizontal. The actual value of the angle of dip is.JEE Mains 2022 Medium
- In the given figure, a mass \(M\) is attached to a horizontal spring which is fixed on one side to a rigid support. The spring constant of the spring is \(k\). The mass oscillates on a frictionless surface with time period \(T\) and amplitude \(A\). When the mass is in equilibrium position, as shown in the figure, another mass \(m\) is gently fixed upon it. The new amplitude of oscillation will be
JEE Mains 2021 Medium - A block of mass 1 kg , moving along x with speed \(\mathrm{v}_{\mathrm{i}}=10 \mathrm{~m} / \mathrm{s}\) enters a rough region ranging from \(\mathrm{x}=0.1 \mathrm{~m}\) to \(\mathrm{x}=1.9 \mathrm{~m}\). The retarding force acting on the block in this range is \(\mathrm{F}_{\mathrm{r}}=-\mathrm{kx} \mathrm{N}\), with \(\mathrm{k}=10 \mathrm{~N} / \mathrm{m}\). Then the final speed of the block as it crosses rough region isJEE Mains 2025 Medium
- A convex lens made of glass (refractive index \(=1.5\) ) has focal length 24 cm in air. When it is totally immersed in water (refractive index \(=1.33\) ), its focal length changes to ________.JEE Mains 2025 Medium
- In a screw gauge when the circular scale is given five complete rotations it moves linearly by \(2.5\) mm. If the circular scale has \(100\) divisions, the least count of screw gauge is _____ mm.JEE Mains 2026 Easy
More PYQs from JEE Mains
- The equivalent capacitance of the combination shown is
JEE Mains 2023 Medium - Two vectors \(\overrightarrow{ A }\) and \(\overrightarrow{ B }\) have equal magnitudes. If magnitude of \(\overrightarrow{ A }+\overrightarrow{ B }\) is equal to two times the magnitude of \(\overrightarrow{ A }-\overrightarrow{ B }\), then the angle between \(\overrightarrow{ A }\) and \(\overrightarrow{ B }\) will be .......................JEE Mains 2022 Medium
- Two identical conducting spheres \(A\) and \(B,\) carry equal charge. They are separated by a distance much larger than their diameter, and the force between them is \(F\) . A third identical conducting sphere, \(C,\) is uncharged. Sphere \(C\) is first touched to \(A,\) then to \(B,\) and then removed. As a result, the force between \(A\) and \(B\) would be equal toJEE Mains 2018 Hard