TS EAMCET · Physics · Ray Optics
The dispersive powers of the materials of two lenses forming an achromatic combination are in the ratio of \(4: 3\). Effective focal length of the two lenses is \(+60 \mathrm{~cm}\) then the focal lengths of the lenses should be
- A \(-20 \mathrm{~cm}, 25 \mathrm{~cm}\)
- B \(20 \mathrm{~cm},-25 \mathrm{~cm}\)
- C \(-15 \mathrm{~cm}, 20 \mathrm{~cm}\)
- D \(15 \mathrm{~cm},-20 \mathrm{~cm}\)
Answer & Solution
Correct Answer
(D) \(15 \mathrm{~cm},-20 \mathrm{~cm}\)
Step-by-step Solution
Detailed explanation
\(\begin{aligned} P=P_1+P_2 & =\frac{q}{f_1}+\frac{q}{f_2} \\ \frac{1}{60} & =\frac{q}{f_1}+\frac{q}{f_2} \\ \frac{1}{60} & =\frac{f_1+f_2}{f_1 f_2}\end{aligned}\) According to question, \(\frac{\omega_1}{\omega_2}=\frac{f_1}{f_2} \Rightarrow \frac{f_1}{f_2}=\frac{-4}{3}\) or…
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
- Consider an expression where are volume, pressure, time, and length respectively. The quantity has dimension is a dimensionless constant. The value of the integer is:TS EAMCET 2021 Medium
- An electron collides with a hydrogen atom in its grownd state and excites it to \(n=3\) state. The energy given to the hydrogen atom in this inelastic collision (neglecting the recoil of hydrogen atom) isTS EAMCET 2017 Easy
- Arectangular coil of 400 turns and \(10^{-2} \mathrm{~m}^2\) area, carrying a current of 0.5 A is placed in a uniform magnetic field of 1 T such that the plane of the coil makes an angle of \(60^{\circ}\) with the direction of the magnetic field. The initial moment of force acting on the coil in Nm isTS EAMCET 2024 Easy
- A ball projected up passes the same height \(\mathrm{H}\) at \(2 \mathrm{~s}\) and \(10 \mathrm{~s}\). The value of \(\mathrm{H}\) is [Use \(\mathrm{g}=9.8 \mathrm{~m} / \mathrm{s}^2\) ]TS EAMCET 2022 Easy
- A man of \(50 \mathrm{~kg}\) is standing at one end on a boat of length \(25 \mathrm{~m}\) and mass \(200 \mathrm{~kg}\). If he starts running and when he reaches the other end, he has a velocity \(2 \mathrm{~ms}^{-1}\) with respect to the boat. The final velocity of the boat is : (in \(\mathrm{ms}^{-1}\) )TS EAMCET 2006 Easy
- The ratio of the centripetal accelerations of the electron in two successive orbits of hydrogen is \(81: 16\). Due to a transition between these two states, the angular momentum of the electron changes by ( \(h\) - Planck's constant)TS EAMCET 2024 Medium
More PYQs from TS EAMCET
- During an adiabatic process, the pressure of a gas is proportional to the cube of its temperature. The value of \(C_p / C_V\) for that gas isTS EAMCET 2011 Medium
- Assertion (A): In a elastic collision of two billiard balls, both kinetic energy and linear momentum remain conserved. Reason (R): During the collision of the balls, as the collision is elastic there is no exchange of energy. Therefore, both energy and momentum are conserved. The correct option among the following isTS EAMCET 2022 Easy
- If the vertical component of earth's magnetic field is \(0.5 \times\) \(10^{-4} \mathrm{~T}\) at a point. When an aeroplane of wing span \(4 \mathrm{~m}\) is moving horizontally at this place at \(360 \mathrm{kmh}^{-1}\), then the motional emf formed across the ends of the wings isTS EAMCET 2023 Hard
- A bar-magnet of moment of inertia \(49 \times 10^{-2} \mathrm{~kg}-\mathrm{m}^2\) vibrates in a magnetic field of induction \(0.5 \times 10^{-4} \mathrm{~T}\). The time period of vibration is \(8.8 \mathrm{~s}\). The magnetic moment of the bar magnet isTS EAMCET 2007 Medium
- As shown in the figure, in a Wheatstone's bridge, three resistances \(\mathrm{P}, \mathrm{Q}\) and \(\mathrm{R}\) are connected in the three arms and the fourth arm is formed by two resistances \(S_1\) and \(S_2\) connected in parallel. The condition for the bridge to be balanced is
TS EAMCET 2023 Hard - A particle of mass \(1 \times 10^{-26} \mathrm{~kg}\) and charge \(1.6 \times 10^{-19} \mathrm{C}\) travelling with a velocity \(1.28 \times 10^6 \mathrm{~ms}^{-1}\) along the positive \(X\)-axis enters a region in which a uniform electric field \(\mathbf{E}\) and a uniform magnetic field of induction \(\mathbf{B}\) are present. If \(\mathbf{E}=-102.4 \times 10^3 \hat{\mathbf{k}} \mathrm{NC}^{-1}\) and \(\mathbf{B}=8 \times 10^{-2} \hat{\mathbf{j}} \mathrm{Wbm}^{-2}\) the direction of motion of the particles isTS EAMCET 2005 Medium