The electron in a hydrogen atom emits wavelengths \( \lambda_1, \lambda_2, \lambda_3, \lambda_4 \) in the following transitions (A), (B), (C), and (D), respectively. Arrange the transitions in the increasing order of emitted wavelengths:
(A) n = 3 to n = 2
(B) n = 4 to n = 3
(C) n = 4 to n = 2
(D) n = 2 to n = 1
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By using Einstein photoelectric equation, if we consider kinetic energy of photo electrons on y-axis and frequency of incident radiation on x-axis. The slope of the graph will represent (the symbols have their usual meanings)

An electron enters a crossed electrical and magnetic field region with a speed of \( 100 \text{ m s}^{-1} \) along \( +x \)-axis and passes undeviated. The strength of magnetic field is 5.0 T and it acts along \( +z \)-axis. Give the electrical field in vector notations indicating its magnitude as well as direction :

From the following diagram, determine the direction of propagation of an electromagnetic wave.

A TV tower has a height of 160 m. How much population is covered by the television broadcast, if the average population density around the tower is 1000 per km^2? Given radius of the earth is 6400 km.

A closed surface in vacuum encloses charges \( - q \) and \( + 3q \). Another charge \( - 2q \) lies out side the surface. The total electric flux over the surface is :

It is observed that only 25% of a given radioactive sample is left undecayed after 16 days. What is the decay constant of the sample in \(\text{day}^{-1}\)?

The system of equations:
\(x+y+z=5\)
\(x+2 y+3 z=9\)
\(x+3 y+\lambda z=\mu\) has a unique solution, if

Select the correctly matched pair about sickle cell anaemia:
Genotype: Phenotype
(A) HbA HbA: Diseased phenotype
(B) HbA Hbs: Diseased phenotype
(C) Hbs Hbs: Diseased phenotype
(D) Hbs HbA: Carrier of disease
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Read the passage carefully and answer the Questions:
According to Valence Bond theory, the metal atom or ion under the influence of ligands can use its ( \(n-1\) )d, \(n s, n p\) or \(n s, n p, n d\) orbitals for hybridisation to yield a set of equivalent orbitals of definite geometry such as octahedral, tetrahedral, square planar and so on. These hybridised orbitals are allowed to overlap with ligand orbitals that can donate electron pairs for bonding. While the VB theory, to a larger extent, explains the formation, structures and magnetic behaviour of coordination compounds, it suffers from the many shortcomings. The Crystal field theory (CFT) is an electrostatic model which considers the metal-ligand bond to be ionic arising purely from electrostatic interactions between the metal ion and the ligand. The five \(d\) orbitals in an isolated gaseous metal atom/ion have same energy, i.e., they are degenerate. This degeneracy is maintained if a spherically symmetrical field of negative charges surrounds the metal atom/lon. However, when this negative field is due to ligands in a complex, it becomes asymmetrical and the degeneracy of the \(d\) orbitals is lifted. It results in splitting of the \(d\) orbitals. The pattern of splitting depends upon the nature of the crystal field.
Which of the following is not true about the limitations of VBT:

The current through a resistor in a circuit is 0.6 A. On putting a resistance of \(2 \Omega\) in parallel with the resistor, the current drops to 0.9 A. The resistance of the resistor is

List-I (Name reaction.)	List-II (Reaction)
(A) Williamson ether synthesis	(I)
(B) Hydroboration oxidation	(II)
(C) Reimer-Tiemann reaction	(III)
(D) Friedel Craft Acylation reaction	(IV)

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In the formation of a Leclanche cell, the space between electrodes is filled with:
(A) \(ZnCl _2\)
(B) \(NH _4 Cl\)
(C) \(AlCl _3\)
(D) ZnS
(E) \(NH _4 NO _3\)
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