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10 months ago

Study Abroad Exam

How to check the availability of PTE exam dates?

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Jiya Arora

Contributor-Level 8

To check the availability of a PTE exam date, visit the official Pearson PTE website and choose your preferred exam according to your purpose of taking the exam. Once you choose your preferred exam, click on "check test availability and book".

From there on, you will be redirected to the "Find an Appointment" page. Enter your preferred nearby location in the search bar and you will get all the PTE test centres the nearest to your entered place. Click on the Calendar dropdown to see the available dates at these test centres; you can also check the available time slots on a given date by checking out the time slot given on the right

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10 months ago

Physics NCERT Exemplar Solutions Class 12th Chapter Ten Physics Ncert Solutions Class 12th

Figure shown a two slit arrangement with a source which emits unpolarised light. P is a polariser with axis whose direction is not given. If I 0 �� 0 is the intensity of the principal maxima when no polariser is present, calculte in the present case, the intensity of the principal maxima as well as the first minima.

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Vishal Baghel

Contributor-Level 10

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

Explanation- when polariser is not used

A=A_perp+A

letA₁= asinwt and A₂=asin(wt+ $\emptyset$ )

now superposition principle for perpendicular polariser

A_R= asinwt+ asin(wt+ $\emptyset$ )

A_R=a(2cos $\emptyset / 2$ sin(wt+ $\emptyset$ ))

A_R=2acos $\emptyset / 2$ sin(wt+ $\emptyset$ )

This eqn is also same for parallel polariser

A_R=2acos $\emptyset / 2$ sin(wt+ $\emptyset$ )

And we know that intensity is directly proportional to square of amplitude

(A_R)²= (A_perp)²+(A)²

So resultant intensity is

I=4(a)²cos^{2
$\emptyset / 2 \frac{1}{T} \int_{0}^{T} {s i n}^{2} (w t + \emptyset)$}dt + 4(a)²cos^{2
$\emptyset / 2 \frac{1}{T} \int_{0}^{T} {s i n}^{2} (w t + \emptyset)$}dt

I= 8(a)²cos^{2
$\emptyset / 2$}(1/2) &nb

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

Explanation- when polariser is not used

A=A_perp+A

letA₁= asinwt and A₂=asin(wt+ $\emptyset$ )

now superposition principle for perpendicular polariser

A_R= asinwt+ asin(wt+ $\emptyset$ )

A_R=a(2cos $\emptyset / 2$ sin(wt+ $\emptyset$ ))

A_R=2acos $\emptyset / 2$ sin(wt+ $\emptyset$ )

This eqn is also same for parallel polariser

A_R=2acos $\emptyset / 2$ sin(wt+ $\emptyset$ )

And we know that intensity is directly proportional to square of amplitude

(A_R)²= (A_perp)²+(A)²

So resultant intensity is

I=4(a)²cos^{2
$\emptyset / 2 \frac{1}{T} \int_{0}^{T} {s i n}^{2} (w t + \emptyset)$}dt + 4(a)²cos^{2
$\emptyset / 2 \frac{1}{T} \int_{0}^{T} {s i n}^{2} (w t + \emptyset)$}dt

I= 8(a)²cos^{2
$\emptyset / 2$}(1/2) (after integrating sin value we got 1/2)

I= 4(a)²cos^{2
$\emptyset / 2$}

So I= 4(a)²

But when there is a polariser

Perpendicular polariser is blocked

I=2(a)²cos^{2
$\emptyset / 2 \frac{1}{T} \int_{0}^{T} {s i n}^{2} (w t + \emptyset)$}dt + (a)^{2
$\frac{1}{T} \int_{0}^{T} {s i n}^{2} (w t)$}

I=2(a)²cos^{2
$\emptyset / 2 +$}1/2(a)²

When $\emptyset = 0$

I_max=2(a)²+1/2(a)²

I_max=5/2(a)²

I_max=5/2(I/4)=5I/8

At first minima it becomes I/8

less

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

Those elements impart colour to the flame on heating in it, the atoms of which require low energy for the ionisation (i.e., absorb energy in the visible region of spectrum). The elements of which of the following groups will impart colour to the flame?

(i) 2

(ii) 13

(iii) 1

(iv) 17

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alok kumar singh

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Option (i) & (iii)

Alkali metals and alkaline earth metals have low ionization enthalpy.

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

In the following questions two or more options may be correct.

Which of the following elements can show covalency greater than 4?

(i) Be

(ii) P

(iii) S

(iv) B

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alok kumar singh

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Option (ii) & (iii)

Both P and S have vacant d-orbital for which they execute extended covalency.

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

Electronic configurations of four elements A, B, C and D are given below:

(A) 1s²2s² 2p⁶ (B) 1s² 2s² 2p⁴

(C) 1s² 2s² 2p⁶ 3s¹ (D) 1s² 2s² 2p⁵

Which of the following is the correct order of increasing tendency to gain electron :

(i) A < C < B < D

(ii) A < B < C < D

(iii) D < B < C < A

(iv) D < A < B < C

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alok kumar singh

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Option (i)

The electron gain enthalpy of 2p orbital is higher than that of the 3s orbital

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10 months ago

M.Sc. IIT Delhi - Indian Institute of Technology

Can I get into IIT Delhi with a rank of 100 in IIT JAM?

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Rashmi Sinha

Contributor-Level 10

IIT Delhi accepts the IIT JAM entrance exam, followed by counselling rounds for MSc admission across various specialisations. For Round 1 admission, the minimum and maximum ranks required for admission ranged from 9 to 513, respectively, for students in the General AI quota. Therefore, if you belong to the general category, you can certainly secure a seat at IIT Delhi. However, students must check which MSc specialisations are available with a cutoff rank of 100 and below, as cutoff ranks differ for various specialisations, ranks, and categories. Tabulated below is the IIT Delhi JAM first round cutoff 2025 for all MSc specialisations,

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10 months ago

M.Tech Computer Science and Engineering

I want to study M.Tech in CSE under 5 Lacs.

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10 months ago

Somaiya School of Humanities and Social Sciences scholarship

Does Somaiya School of Humanities and Social Sciences offer scholarships to students?

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Nishtha Singh

Contributor-Level 10

Somaiya School of Humanities and Social Sciences awards various scholarships to students as financial assistance. To be eligible for the financial aid, applicants must fulfill any one of the following criteria:

EWS/BPL: Applicants with family income up to INR 8 LPA are eligible for financial Aid up to 100% concession on the available tuition fees.
Defence Personnel: Wards of defence personnel deceased or disabled in the line of duty may receive a 50% concession on the available tuition fees.

PWD: Applicants with benchmark disabilities (40% or even more) are eligible for a 50% concession on the available tuition fees.

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10 months ago

Neelkanth Group of Institutions Colleges in India

What are the important dates associated with BTech admission at Neelkanth Group of Institutions?

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Himanshu Singh

Contributor-Level 10

For 2025 BTech admissions through UPTAC, key dates include registration, fee payment, and document upload from May 27 to June 30. Document verification and query response rounds are expected to take place between June and July, followed by choice filling, seat allotment, and confirmation rounds in August. Students should regularly check official updates to stay informed about changes in the UPTAC schedule.

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10 months ago

Ahmedabad Business School

How can I apply for admission at Ahmedabad Business School?

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10 months ago

Neelkanth Group of Institutions Colleges in India

Is the admission open for the BTech programme at Neelkanth Group of Institutions?

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Himanshu Singh

Contributor-Level 10

Yes, admissions for the BTech programme at Neelkanth Group of Institutions are currently open. Interested candidates who meet the eligibility criteria are encouraged to apply at the earliest. It is advisable to stay updated with official announcements regarding application deadlines and entrance exam requirements.

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10 months ago

IIT Gandhinagar - Indian Institute of Technology Colleges in Ahmedabad

What is the cutoff of IIT Gandhinagar for 2025 admission?

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Akanksha Arora

Contributor-Level 6

IIT Gandhinagar cutoff 2025 has been released for admission to MSc specialisations. The closing ranks in the round 1 were between the range of 338 and 396. The cutoff was released for MSc in Chemistry, MSc in Mathematics and MSc in Physics. The round 1 closing ranks for the above specialisations were 358, 396 and 338.

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

Comprehension given below is followed by some multiple choice questions. Each question has one correct option. Choose the correct option.

In the modern periodic table, elements are arranged in order of increasing atomic numbers which is related to the electronic configuration. Depending upon the type of orbitals receiving the last electron, the elements in the periodic table have been divided into four blocks, viz, s, p, d and f. The modern periodic table consists of 7 periods and 18 groups. Each period begins with the filling of a new energy shell. In accordance with the Arfbau principle, the seven periods (1 to 7) have 2, 8, 8, 18,

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alok kumar singh

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Option (iii) d-block

Lanthanum is the element with the atomic number 57 and it belongs to the d-block.

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10 months ago

MBSE HSSLC Exam

I skipped my pre board exam. Can my school deny my MBSE HSSLC 12th board exam hall ticket?

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Salviya Antony

Contributor-Level 10

No, your school cannot deny you the MBSE 12th admit card even if you have skipped the pre-boards exam. If they still goes on to deny you the hall ticket you can straight away write it to the board asking them to issue your 12th hall ticket in duplicate as your school has failed to give you. Hall ticket for the MBSE 12th board exam is issued by the Mizoram Board of School Education (MBSE).

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10 months ago

MBSE HSSLC Exam

Should I keep the MBSE 12th hall ticket till the release of the results?

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Salviya Antony

Contributor-Level 10

Students are advised to keep the MBSE 12th hall ticket till the release of the results. The MBSE 12th hall ticket contains the register number of the candidate. Thus student can easily check the MBSE 12th result using the register number.

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

The formation of the oxide ion, O^2– (g), from oxygen atom requires first an exothermic and then an endothermic step as shown below:

O_(g) + e^–→ O^–(g) ; ∆ Hᶱ = – 141 kJ mol^–1

O^– (g) + e^–→ O^2– (g); ∆ Hᶱ = + 780 kJ mol^–1

Thus process of formation of O^2– in gas phase is unfavourable even though O^2– is isoelectronic with neon. It is due to the fact that,

(i) Oxygen is more electronegative.

(ii) Addition of electron in oxygen results in larger size of the ion.

(iii) Electron repulsion outweighs the stability gained by achieving noble gas c

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alok kumar singh

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Option (iii)

High amount of energy has to be supplied in order to overcome the e^- - e^- repulsion that arises when O^- gets converted to O^2- by accepting an electron

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

Which of the following is the correct order of size of the given species:

(i) I > I ^– > I ⁺

(ii) I ⁺ > I ^– > I

(iii) I > I ⁺ > I ^–

(iv) I ^– > I > I⁺

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alok kumar singh

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Option (iv)

I⁺ possess the highest effective nuclear charge whereas I^-possess the least among the given species.

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10 months ago

Physics NCERT Exemplar Solutions Class 12th Chapter Twelve Physics Ncert Solutions Class 12th

The simple Bohr model is not applicable to He⁴atom because
(a) He⁴ is an inert gas
(b) He⁴ has neutrons in the nucleus
(c) He⁴ has one more electron
(d) Electrons are not subject to central forces

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Vishal Baghel

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- (c, d)

Explanation- The simple Bohr model is not applicable to He⁴ atom because He⁴ has one more electron and electrons are not subject to central forces.

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10 months ago

Physics NCERT Exemplar Solutions Class 12th Chapter Twelve Physics Ncert Solutions Class 12th

Let E_n= $\frac{- 1 m e^{4}}{8 ε_{0}^{2} n^{2} h^{2}}$ be the energy of the nth level of H atom. If all the H-atoms are in the ground state and radiation of frequency $\frac{E_{2} - E_{1}}{h}$ falls on it

(a) It will not be absorbed at all

(b) Some of atoms will move to first excited state

(c) All atoms will be excited to the n= 2 state

(d) No atoms will make a transition to then n=3 state

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Vishal Baghel

Contributor-Level 10

This is a Multiple Choice Questions as classified in NCERT Exemplar

Answer- (b, d)

Explanation- when a radiation of energy fall on it some atoms would be excited but not all would be excite also no atom will go to 3 level some go to 2 level also but not all excite to 2 level. So by considering these facts we can say b and d option are correct

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10 months ago

Chemistry NCERT Exemplar Solutions Class 11th Chapter Three Classification of Elements and Periodicity in Prop

The elements in which electrons are progressively filled in 4f-orbital are called

(i) Actinoids

(ii) Transition elements

(iii) Lanthanoids

(iv) Halogens

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