A free electron is placed in the path of a plane electromagnetic wave. The electron will start moving -

\( p \rightarrow n + \nu + A \) In this nuclear reaction A is a/an:

Rohit has been given two converging lenses of focal lengths 1.25 cm and 5 cm, respectively to design a compound microscope. If it is desired to have a magnification of 30, what would be the separation between the objective and the eyepiece when the final image is formed at the least distance of distinct vision?

An electric dipole of length 4 cm, when placed with its axis making an angle of \( 60^{\circ} \) with a uniform electric field, experiences a torque of \( 4\sqrt{3} \text{ N m} \). If the dipole has charges of \( \pm 8 \text{ nC} \), then the potential energy of the dipole in the electric field is:

The intensity ratio of two interfering sources in Young's double slit experiment is \(4 : 1\). The ratio of \( \frac{I_{min}}{I_{max}} \) is:

A rod of 20 cm lying along the horizontal East-West direction falls freely from the roof of a building of height 3 m. If the horizontal component of the Earth's magnetic field is 0.36 G over the region, find the magnitude of Induced emf when it reaches the bottom of the building (take \( g = 10 \text{ m/s}^2 \) at that place)

Which of the following phenomena proves the particle nature of photon ?

Relation \(R\) on Real Numbers is defined as \(R =\{( a , b ): a \leq b \}\). The relation is :

Based on CFT, in octahedral crystal field, d orbitals split into orbitals of \(t_{2g}\) and \(e_{g}\) sets. Which d orbitals forms the \(t_{2g}\) set?

The forbidden energy gaps in conductors, semiconductors and insulators are \( (E_g)_c, (E_g)_s \) and \( (E_g)_I \) respectively. What is the relation among them ?

A parallel plate capacitor having area A and separated by distance d is filled by copper plate of thickness b. The new capacitance is:

Identify the correct relation between the molar mass of solute and Ebullioscopic constant.

Read the passage carefully and answer the Questions
Werner in 1898, propounded his theory of coordination compounds. In coordination compounds metals show two types of linkages (valences)-primary and secondary. The primary valences are normally ionisable and are satisfied by negative ions. The secondary valences are non-ionisable. These are satisfied by neutral molecules or negative ions. The secondary valence is equal to the coordination number and is fixed for a metal. The ions or group bound by the secondary linkages to the metal have characteristic spatial arrangements corresponding to the different coordination numbers. Both double salts as well as complexes are formed by the combination of two or more stable compounds in stoichiometric ratio. However, they differ in the fact that double salts such as carnallite, Mohr's salt, potash alum etc. dissociate into simple ions completely when dissolved in water. But complex ions do not dissociate completely into simple ions.
Which of the following is a double salt?