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In Young’s double slit arrangement, slits are separated by a gap of \( 0.5 \, \text{mm} \), and the screen is placed at a distance of \( 0.5 \, \text{m} \) from them. The distance between the first and the third bright fringe formed when the slits are illuminated by a monochromatic light of 5890 Å is:

The light waves from two coherent sources have same intensity \( I_1 = I_2 = I_0 \). In interference pattern the intensity of light at minima is zero. What will be the intensity of light at maxima?

In Young’s double slit experiment, if the source of light changes from orange to blue then:

In a Young's double slit experiment, the slits are separated by \( 0.3 \, \text{mm} \) and the screen is \( 1.5 \, \text{m} \) away from the plane of slits. Distance between fourth bright fringes on both sides of central bright fringe is \( 2.4 \, \text{cm} \). The frequency of light used is ______ \( \times 10^{14} \, \text{Hz} \) .

The width of one of the two slits in a Young’s double slit experiment is three times the other slit. If the amplitude of the light coming from a slit is proportional to the slit-width, the ratio of minimum to maximum intensity in the interference pattern is \( x : 4 \) where \( x \) is:

Red light differs from blue light as they have:

In the Young's double slit experiment, the distance between the slits varies in time as \( d(t)=d_0+a_0 \sin \omega t \) where \( d_0, \omega \) and \( a_0 \) are constants. The difference between the largest fringe width and the smallest fringe width obtained over time is given as:

White light is passed through a double slit and interference is observed on a screen \( 1.5 \, \text{m} \) away. The separation between the slits is \( 0.3 \, \text{mm} \). The first violet and red fringes are formed \( 2.0 \, \text{mm} \) and \( 3.5 \, \text{mm} \) away from the central white fringes. The difference in wavelengths of red and violet light is ______ \( \text{nm} \).

A source of light is placed in front of a screen. Intensity of light on the screen is \( I \). Two Polaroids \( P_1 \) and \( P_2 \) are so placed in between the source of light and screen that the intensity of light on screen is \( \dfrac{I}{2} \). \( P_2 \) should be rotated by an angle of __________ (degrees) so that the intensity of light on the screen becomes \( \dfrac{3I}{8} \).

A linearly polarized electromagnetic wave in vacuum is \( \vec{E}=3.1\cos\!\left[(1.8)z-(5.4\times 10^{6}) t\right]\\,\hat{i}\ \text{N}/\text{C} \) is incident normally on a perfectly reflecting wall at \( z=a \). Choose the correct option

The difference in the number of waves when yellow light propagates through air and vacuum columns of the same thickness is one. The thickness of the air column is ______ \( \text{mm} \).
[Refractive index of air = \( 1.0003 \), wavelength of yellow light in vacuum = \( 6000 \, \mathring{A} \)]

If the source of light used in a Young’s double slit experiment is changed from red to violet:

With what speed should a galaxy move outward with respect to earth so that the sodium-D line at wavelength \( 5890 \, \displaystyle \overset{\circ}{\text{A}} \) is observed at \( 5896 \, \displaystyle \overset{\circ}{\text{A}} \) ?

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JEE Main 2021 20th July Evening Shift

With what speed should a galaxy move outward with respect to earth so that the sodium-D line at wavelength \( 5890 \, \displaystyle \overset{\circ}{\text{A}} \) is observed at \( 5896 \, \displaystyle \overset{\circ}{\text{A}} \) ?