A planoconvex lens has the radius of curvature of its curved surface 50 cm and the refractive index of its material is 1.5. Its focal length will be

What uniform magnetic field applied perpendicular to a beam of electrons moving at \( 1.3 \times 10^6 \text{ m/s} \) is required to make the electrons travel in a circular arc of radius 0.35 m?

The nuclear force is:

The equivalent resistance between P and Q is:

A steady current flows in a metallic conductor of non-uniform cross-section. The quantity that is constant along the length is

The condition for observing diffraction from a single slit is that the light wavefront incident on the slit should be

Match List I with List - II.,

List - I	List - II
(A) TV Transmission	(I) Short wave bands
(B) Long distance radio broadcasts	(II) Microwave
(C) RADAR	(III) Infrared rays
(D) TV Remote	(IV) Satellite

Choose the correct answer from the options given below :

The angle between the straight lines \(\frac{x+4}{2}=\frac{y+5}{5}=\frac{z+6}{3}\) and \(\frac{x-4}{10}=\frac{y-5}{2}=\frac{z-6}{-10}\) is:

0.04 F of charge will liberate how much of oxygen gas (at STP) from acidified water?

Read the passage carefully and answer
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. Ligands are treated as point charges in case of anions or dipoles in case of neutral molecules. 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/ion. However, when this negative field is due to ligands (either anions or the negative ends of dipolar molecules like NH3 and H2O) in a complex, it becomes asymmetrical and the degeneracy of the dorbitals is lifted. It results in splitting of the d orbitals. The pattern of splitting depends upon the nature of the crystal field.
The colour of coordination compounds is attributed to

If \(\left|\begin{array}{ccc}-a^2 & a b & a c \\ a b & -b^2 & b c \\ a c & b c & -c^2\end{array}\right|=\lambda a^2 b^2 c^2\), then the value of \(\lambda\) is:

A part of an infinitely long current carrying wire is bent into a circular shape as shown in the diagram. The magnetic field at the centre of the circle is

Van Arkel Method is used for -