A convex lens of focal length 40 cm is in contact with a concave lens of focal length 25 cm. The power of the combination is
- - 1.5 D
- -6.5 D
- + 6.5 D
- + 6.67 D
The Correct Option is A
Solution and Explanation
Top Questions on Ray optics and optical instruments
- Two equilateral-triangular prisms \(P_1 \)and \(P_2\) are kept with their sides parallel to each other, in vacuum, as shown in the figure. A light ray enters prism \(P_1\) at an angle of incidence π such that the outgoing ray undergoes minimum deviation in prism \(P_2\). If the respective refractive indices of \(P_1\) and\( P_2\) are \(β 3 /2\) and \(β3\), then \(\theta = sin{β1}[\sqrt \frac{ 3}{ 2} sin ( \frac{\pi}{B} )],\) where the value of \(\beta\) is ______.
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Monochromatic light wave
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Questions Asked in JEE Advanced exam
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Which of the following graph best depicts the variation of the induced emf (E) in the loop as a function of the distance (π₯) starting from π₯ = 0? - Two beads, each with charge q and mass m, are on a horizontal, frictionless, non-conducting, circular hoop of radius R. One of the beads is glued to the hoop at some point, while the other one performs small oscillations about its equilibrium position along the hoop. The square of the angular frequency of the small oscillations is given by [ \(\epsilon_0 \)is the permittivity of free space.]
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Concepts Used:
Ray Optics and Optical Instruments
Optics, deals with the determination of behaviour and the properties of light, along with its interactions with the matter and also with the instruments that are used to detect it.
Ray optics is also known as the geometrical optics and it is a branch of science which describes light propagation.
Reflection is the change in direction of light at an interface in-between two different media so that the wave-front returns into a medium from which it was originated.
Speed of light is the rate at which the light travels in free space.
A phenomenal change in image formed when the light is passed from one medium to another which is called Refraction.
Total Internal Reflection is the reflection of light when the light ray enters into a rarer medium from a denser medium and the angle of incidence is higher than the critical angle of incidence then that light ray will be reflected back to the denser medium.
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