The necessary conditions for total internal reflection are
(A) Light must travel from denser to rarer medium.
(B) The angle of incidence in the denser medium must be less than the critical angle for the two media.
(C) Light must travel from rarer to denser medium.
(D) The angle of incidence in the denser medium must be greater than the critical angle for the two media.
Choose the correct answer from the options given below:

Given below are two statements :
Statement (I) : In a ground wave communication system, low frequency signal (< 2 MHz) can be transmitted.
Statement (II) : If frequency is high then it will induce electrical signal on the surface of the earth and so attenuation takes place.
In the light of the above statements, choose the most appropriate answer from the options given below :

In uniform electric field \( \vec{E} = 3 \times 10^3\hat{i} \text{ N/C} \), a square loop of side 10 cm is placed such that plane of square loop is parallel to the yz plane. The flux linked with the square loop will be:

A concave lens and a convex mirror both are dipped in an oil of refractive index 1.2. The focal length of:

A solenoid with an iron core and a bulb in series are connected to a d.c. source. When the iron core is removed from the solenoid, the brightness of the bulb will

A photon has a momentum of \(3.3 \times 10^{-29} kg m / s\). The frequency of the waves associated with the photon will be (Given: \(h=6.6 \times 10^{-84} Js\) )

A cell of emf \( \mathcal{E} = 10 \text{ V} \) and internal resistance \( r = 3 \Omega \) is connected to a uniform wire of length \( L = 500 \text{ cm} \) and resistance \( R = 3 \Omega \). The drop of potential with length in the wire is:

Select one of the given options which includes all sexually transmitted infections.

Read the passage given below and answer the question.
The transition elements which give the greatest number of oxidation states occur in or near the middle of the series. Manganese, for example, exhibits all the oxidation states from +2 to +7. The lesser number of oxidation states at extreme ends stems from either too few electrons to lose or share (Sc, Ti) on too many d-electrons (hence fewer orbitals available in which to share electrons with others) for higher valence (Cu, Zn). Thus early in the series scandium (II) is virtually unknown and titanium (IV) is more stable than Ti (III) or Ti (II). At the other end, the only oxidation state of zinc is +2 (no d electrons are involved). The maximum oxidation states of reasonable stability correspond in value to the sum of the s- and d-electrons upto manganese (\(TiO_2, VVO^+, CrVIO_4^{2-}, MnVIIO_4\)) followed by a rather abrupt decrease in stability of higher oxidation states, so that the typical species to follow are \(Fe^{II,III}, Co^{II,III}, Ni^{II}, Cu^{I,II}, Zn^{II}\).
The variability of oxidation states, a characteristic of transition elements, arises out of incomplete filling of d-orbitaIs in such a way that their oxidation states differ from each other by unity, e.g. \(V ^{I I}, V^{I I I}, V^{I V}, V^V\). This is in contrast with the variability of oxidation states of non transition elements where oxidation states normally differ by a unit of two.
An interesting feature in the variability of oxidation states of the d-block elements is noticed among the groups (groups 4 through 10). Although in the p-block, the lower oxidation states are favoured by the heavier members (due to inert pair effect), the opposite is true in the groups of dblock. For example, in group 6, Mo(VI) and W(VI) are found to be more stable than \(Cr ( VI )\). The \(Cr ( VI )\) in the form of dichromate in acidic medium is a strong oxidising agent, whereas \(MoO _3\) and \(WO _3\) are not.
Low oxidation states are found when a complex compound has ligands capable of \(\pi\)-acceptor character in addition to the \(\sigma\)-bonding. For example, in \(Ni ( CO )_4\) and \(Fe ( CO )_5\), the oxidation state of nickel and iron is zero.
Highest oxidation state shown by 'Mn' is :

The function \(f(x)=\tan x-x\) for \(x \in\left(0, \frac{\pi}{2}\right)\) is :

Identify the statements which are true with respect to colour blindness
A. Sex-linked recessive disorder
B. Sufferers are unable to differentiate between red or green colour
C. It occurs in 8% males and 0.4% females.
D. The defect is due to the mutation in genes present on 'Y' chromosome
Choose the correct answer from the options given below:

To convert a galvanometer into an ammeter

Match List I with List - II. -

List - l	List - II
(A) Francis Crick	(l) DNA is the genetic material
(B) Watson and Crick	(II) Transforming principle
(C) Hershey and Chase	(III) Central dogma in molecular biology
(D) Frederick Griffith	(IV) Double helical structure of DNA

Choose the correct answer from the options given below: