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This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- T₂P= T₂O+OP= D+x

T₁P= T₁O-OP= D-x

S₁P $\frac{\mathit{\lambda }}{2}$ = $\sqrt[]{{{(S}_1{T}_1)}^2+{\left(P{T}_1\right)}^2}=\sqrt[]{D^2+{(d-x)}^2}$

S₂P= $\sqrt[]{{{(S}_2{T}_2)}^2+{\left(P{T}_2\right)}^2}=\sqrt[]{D^2+{(d+x)}^2}$

The minima will occur when S₂P- S₁P= (2n-1) $\frac{\mathit{\lambda }}{2}$

$\sqrt[]{D^2+{(d+x)}^2}$ - $\sqrt[]{D^2+{(d-x)}^2}$ = $\frac{\mathit{\lambda }}{2}$

$x=D$

[D²+4D²]^1/2-[D²+0]^1/2= $\frac{\mathit{\lambda }}{2}$

[5D²]^1/2- [D²]^1/2= $\frac{\mathit{\lambda }}{2}$

$\sqrt[]{5}$ D-D= $\frac{\mathit{\lambda }}{2}$

$\mathrm{a}\mathrm{f}\mathrm{t}\mathrm{e}\mathrm{r}\mathrm{}\mathrm{s}\mathrm{o}\mathrm{l}\mathrm{v}\mathrm{i}\mathrm{n}\mathrm{g}$ we get D= 0.404 $\mathit{\lambda }$

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- resolving power =1/d = $\frac{2sin\beta }{1.22\lambda }$  = d_min= $\frac{1.22\lambda }{2sin\beta }$  where $\lambda$  is the wavelength of light

So d_min= $\frac{1.22\times 5500\times {10}^{-10}}{2sin\beta }$

$\lambda$ = $\frac{12.27}{\sqrt[]{V}}$ = 0.12 $\times$ 10^-9m

$\frac{d\text{'}min}{dmin}$ = $\frac{0.12\times {10}^{-9}}{5500\times {10}^{-10}}$ = 0.2 $\times$ 10^-3

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- When angle of incidence is equal to Brewster’s angle, the transmitted light is unpolarised and reflected light is plane polarised.

Consider the diagram in which unpolarised light is represented by dot and plane polarised light is represented By arrows.

Polarisation by reflection occurs when the angle of incidence Is the Brewster’s angle

So tani_b = $\frac{{\mu }_1}{{\mu }_2}$  where $\mu$ ₂< $\mu$ ₁

When the light rays travels in such a medium, the critical angle is

Sini_c= $\frac{{\mu }_2}{{\mu }_1}$

Where $\mu$ ₂< $\mu$ ₁

As tani_b > sini_c for large angles i_bc

Thus the polarisation by reflection occurs definitely.

No, direct admission is not valid at Oriental College of Management. Admission to Oriental College of Management is based on several factors, including qualifying entrance exams and must complete graduation with a 50% aggregate (45% for reserve category).

The IIT Delhi MSc cutoff 2025 via IIT JAM has been released for different categories of students within the AI quota. The cutoffs were published as opening and closing ranks for various MSc specialisations. For OBC category students, the first-round cutoff ranks ranged from 60 to 986. Therefore, candidates seeking admission must aim to secure a minimum rank of 60 or lower to be eligible for MSc admission at IIT Delhi. However, aspirants should note that cutoff ranks differ across various rounds, categories, and specialisations. Below is the IIT JAM Round 1 cutoff list for 2025 for OBC AI category students. 

ABS course admission is completely merit-based & entrance exam-based. Students seeking to apply for any of the courses offered at the college must fulfil the admission criteria of the desired programme before applying for it. Further, candidates seeking admission to the BBA programme must be Class 12 passed from a recognised board. 

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Option (ii)

The electron gain enthalpy decreases down the group due to the increase in the atomic size which leads to decrease in the effective nuclear charge.

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- angular resolution of the eye? = 5.8 x 10^-4

linear distance between two dots is l= 2.54/300=0.84 $\times$ 10^-2cm

? = l/z

z=l/? = $\frac{0.84\times {10}^{-2}}{5.8\times {10}^{-4}}$ = 14.5cm

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- As we know that the frequencies of sound waves lie between 20 Hz to 20 kHz so that their wavelength ranges between 15 m to 15 mm. The diffraction occur if the wavelength of waves is nearly equal to slit width.

As the wavelength of light waves is 7000 ×10^-10 m to 4000 $\times$ 10^-10m. The slit width is very near to the wavelength of sound waves as compared to light waves. Thus, the diffraction of sound waves is more evident in daily life than that of light waves.

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Option (iii)

The Be has the electronic configuration of [He]2s² while B has the electronic configuration of [He]2s²2p¹ . As in Be the outermost orbital i.e. 2s is fully filled thus it provides extra stability to the Be compared to B. Apart from this 2s electron is more penetrated compared to the 2p electron for which 2p electron faces more shielding effect than that of 2s electron.

This is a Short Answer Type Questions as classified in NCERT Exemplar
Explanation- We know that the sun is at very large distance from the earth. Assuming sun as spherical, it can be considered as point source situated at infinity. Due to the large distance the radius of wavefront can be considered as large (infinity) and hence, wavefront is almost plane.

This is a Assertion and Reason Type Questions as classified in NCERT Exemplar

Option (ii)

The ionization energy depends upon two factors

(a) The effective nuclear charge.

(b)The e^- -e ^– repulsions.

This is a Short Answer Type Questions as classified in NCERT Exemplar

Explanation- The point image I₁, due to L₁ is at the focal point. Now, due to the converging lens L₂, let final image formed is I which is point image, hence the wavefront for this image will be of spherical symmetry.