Physics · 2017
NEET 2017 · 7 May · Code A · Q42
A beam of light from a source L is incident normally on a plane mirror fixed at a certain distance x from the source. The beam is reflected back as a…
A beam of light from a source $\displaystyle L$ is incident normally on a plane mirror fixed at a certain distance $\displaystyle x$ from the source. The beam is reflected back as a spot on a scale placed just above the source $\displaystyle L$. When the mirror is rotated through a small angle $\displaystyle \theta$, the spot of the light is found to move through a distance $\displaystyle y$ on the scale. The angle $\displaystyle \theta$ is given by :
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle \frac{y}{2 x}$
More from Ray Optics and Optical Instruments
- In the figure shown here, what is the equivalent focal length of the combination of lenses (Assume that all layers are thin)?2023
- Assume that light of wavelength 600 nm is coming from a star. The limit of resolution of telescope whose objective has a diameter of 2 m is:2020
- Two transparent media A and B are separated by a plane boundary. The speed of light in those media are 1.5 × 10^8 m / s and 2.0 × 10^8 m / s,…2022
- A thin prism having refracting angle 10° is made of glass of refractive index 1.42. This prism is combined with another thin prism of glass of…2017
- Two similar thin equi-convex lenses, of focal length f each, are kept coaxially in contact with each other such that the focal length of the…2019
- A convex lens 'A' of focal length 20 cm and a concave lens 'B' of focal length 5 cm are kept along the same axis with a distance 'd' between them. If…2021
- A lens of large focal length and large aperture is best suited as an objective of an astronomical telescope since:2021
- In a certain camera, a combination of four similar thin convex lenses are arranged axially in contact. Then the power of the combination and the…2025
NEET (UG) 2017 Physics question, with the answer from NTA’s final answer key. Where our answers come from.