A lens of power +3.5 diopters is placed in contact with a lens of power -2.5 diopter. The combination will behave like:
- A convergent lens of focal length 100 cm
- A divergent lens of focal length 100 cm
- A convergent lens of focal 200 cm
- A divergent lens of focal length 200 cm
The Correct Option is C
Solution and Explanation
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- A thin prism \( P_1 \) with angle \( 4^\circ \) made of glass having refractive index 1.54 is combined with another thin prism \( P_2 \) made of glass having refractive index 1.72 to get dispersion without deviation. The angle of the prism \( P_2 \) in degrees is:
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Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R):
Assertion (A): An electron in a certain region of uniform magnetic field is moving with constant velocity in a straight line path.
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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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