In Young’s double slit experiment, the fringe width is 12 mm. If the entire arrangement is placed in water of refractive index \(\frac 43\), then the fringe width becomes (in mm)
- 16
- 9
- 48
- 12
The Correct Option is B
Solution and Explanation
\(B = 12× 10^-3\)
\(β'=\frac βμ\)
\(β'=\frac {12×10^{−3}}{\frac 43}\)
\(β'= 9 × 10^{-3} m\)
\(β'= 9\ mm\)
So, the correct option is (B): \(9\).
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Concepts Used:
Polarisation
Light travels in form of transverse EM waves. The underlying oscillation is along directions perpendicular to the propagation direction, in this example, oscillating electric and magnetic fields. Process of restricting the vibration of light waves to one direction is known as Polarisation.
Types of Polarisation:
There are three types of polarisation such as:
- Linear Polarisation in the electric field of light is limited to one single plane that is along the direction of propagation.
- Elliptical Polarisation: In this, both the phase difference and amplitude between the two linear components are not equal.
- Circular Polarisation: The electric field of light follows a circular propagation. The two linear components that exist in the electric field are the same amplitudes but have different phase differences.
Methods of Polarisation of Light:
The few methods of polarisation of Light are:
- Polarization by dispersing
- Polarization by Reflection
- Polarization by Refraction
- Polarization By Transfer