Which one of the alkali metals, forms only, the normal oxide, on heating in air?
In which of the following reactions, standard entropy change is positive and standard Gibb's energy change decreases sharply with increasing temperature?
Aluminium is extracted from alumina by electrolysis of a molten mixture of:
The enthalpy of fusion of water is 1.435 kCal/mol. The molar entropy change for the melting of ice at is:
A car of mass m starts from rest and accelerates so that the instantaneous power delivered to the car has a constant magnitude . The instantaneous velocity of this car is proportional to
Which nomenclature is not according ti IUPAC system?
The moment of inertia of a uniform circular disc is maximum about an axis perpendicular to the disc and passing through
ABC is an equilateral triangle with O as its centre. represent three forces acting along the sides AB, BC and AC respectively. If the total torque about O is zero the magnitude of
Three masses are placed on the x-axis: 300 g at origin, 500 g at x=40 cm and 400 g at x=70 cm. The distance of the centre of mass from the origin is
If n1, n2 and n3 are the fundamental frequencies of three segments into which a string is divided, then the original fundamental frequency n of the string is given by:
A circular platform is mounted on a frictionless vertical axle. Its radius R=2m and its moment of inertia about the axle is 200 kgm. It is initially at rest. A 50 kg man stands on the edge of the platform and begins to walk along the adge at the speed of 1 relative to the ground. Time taken by the man to complete one revolution is
Two similar coils of radius r are lying concentrically with their planes at right angles to each others. The currents flowing in them are , respectively. The resultant magnetic field induction at the centre will be:
An -particle moves in a circular path of radius 0.83cm in the presence of a magnetic field of . The wavelength associated with the particle will be:
The current (I) in the inductance is varying with time according to the plot shown in figure.
Which one of the following is the correct variation of voltage with time in the coil?