The ratio of velocity of light in vacuum to that of velocity of light in medium is: (where symbols have their usual meanings).

An electric source has an emf of 130 V and a terminal voltage of 110 V. If it supplies a terminal current of 20 A, its internal resistance will be

A point source S is placed at a distance of 12 cm from a converging lens of focal length 10 cm on its principal axis. Where should a diverging mirror of focal length 14 cm be placed from the lens so that a real image is formed on the source itself?

A bar magnet of magnetic moment 5.0 \( A \, m^2 \) has poles 20 cm apart. The pole strength would be

Two similar coils of radius R are lying concentrically with their planes perpendicular to each other and carrying current I and 2I respectively. What is the resultant magnetic field at the center?

A plane electromagnetic wave of frequency 50 MHz travels in free space along the x-direction. At a particular point in space and time \( \vec{E} = 9.3 \hat{j} \text{ V m}^{-1} \). What is \( \vec{B} \) at this point?

The capacitance of a capacitor becomes \( \frac{9}{7} \) times of its original value when a dielectric slab of thickness \( t = \frac{d}{4} \) is inserted between the plates, where d is the separation between the plates. The dielectric constant of the slab is

Answer the question on basis of passage given below :
Molecular nitrogen is very little reactive chemically. During lightning discharge, atmospheric nitrogen and oxygen combines to form nitric oxide which also combines with oxygen to form nitrogen dioxide. Both NO and \(NO _2\) constitute smog which is very poisonous. It can cause burning sensation in the eyes and adversely affect respiratory system.
What is the value associated with control of photo chemical smog?

If \(\left|\begin{array}{cc}3 x & 4 \\ 7 & x\end{array}\right|=\left|\begin{array}{ll}6 & 3 \\ 2 & 1\end{array}\right|\) then :

Question based on the following passage: P-Block elements are placed in group 13 to 18 in the periodic table. Group 15 is nitrogen family.
Nitrogen can react with hydrogen, oxygen, halogens etc. It shows multiple oxidation states in its various oxides i.e. \(N_2O, N_2O_3, N_2O_5\) etc. Important allotropic forms of phosphorus are white, red and black phosporus. Various compounds of phosphorus are phosphine, \(PCl_3, PCl_5\) and oxoacids of phosphorus. Oxidation states \(+1\) to \(+5\) are seen in various oxoacids of phosphorus. Group 17 elements are collectively known as halogens. Bond dissociation enthalpy of \(F_2\) is smaller than \(Cl_2\).
The gases present in group 18 are chemically unreactive, they form only few compounds. Neil Bartlett (in 1962) observed the reaction of a noble gas. Since then, many noble gas compounds have been synthesised.
Explosive nature of fluorine (\(F_2\)) is due to:

Arrange the following step of PCR in correct sequence.
(A) Extension of Primer
(B) Annealing
(C) Denaturation of ds DNA
(D) Amplification
(E) Use of DNA polymerase and deoxynucleotides
Choose the correct answer from the options given below:

The energy equivalent of 10 g of substance is:

Choose the correct statement from the options given below: