A rod of length $2 \,cm$ makes an angle $\frac{2 \pi}{3}$ rad with the principal axis of a thin convex lens The lens has a focal length of $10\, cm$ and is placed at a distance of $\frac{40}{3} cm$ from the object as shown in the figure The height of the image is $\frac{30 \sqrt{3}}{13} cm$ and the angle made by it with respect to the principal axis is $\alpha rad$ The value of $\alpha$ is $\frac{\pi}{n} rad$, where $n$ is ___
A rod of length $2 \,cm$ makes an angle $\frac{2 \pi}{3}$ rad with the principal axis of a thin convex lens The lens has a focal length of $10\, cm$ and is placed at a distance of $\frac{40}{3} cm$ from the object as shown in the figure The height of the image is $\frac{30 \sqrt{3}}{13} cm$ and the angle made by it with respect to the principal axis is $\alpha rad$ The value of $\alpha$ is $\frac{\pi}{n} rad$, where $n$ is ___
Solution and Explanation
Top Questions on Ray optics and optical instruments
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Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R):
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- A long straight wire of a circular cross-section with radius \( a \) carries a steady current \( I \). The current is uniformly distributed across this cross-section. The plot of magnitude of magnetic field \( B \) with distance \( r \) from the centre of the wire is given by:
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Questions Asked in JEE Advanced exam
- A positive, singly ionized atom of mass number \( A_M \) is accelerated from rest by the voltage \( 192 \, \text{V} \). Thereafter, it enters a rectangular region of width \( w \) with magnetic field \( \vec{B}_0 = 0.1\hat{k} \, \text{T} \). The ion finally hits a detector at the distance \( x \) below its starting trajectory. Which of the following option(s) is(are) correct? \[ \text{(Given: Mass of neutron/proton = } \frac{5}{3} \times 10^{-27} \, \text{kg, charge of the electron = } 1.6 \times 10^{-19} \, \text{C).} \]
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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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