List of practice Questions

A particle executes simple harmonic motion with amplitude A. The distance moved by the particle in one oscillation is
The current in a coil changes from 1 mA to 5 mA in 4 ms. ? If the coefficient of self-inductance of the 'coil is 10 mH,. the magnitude of "self-induced" emf is?
The atomic number of the element with highest ionization energy among the following is
The heat of formation of $ {H_2O_{(l)}}$ is -286 kJ. The? heat of formation of $ { H_2O_{(g)}}$ is likely to be
A block of mass 0.1 kg is held against a wall by applying a horizontal force of 5 N on it. If $\mu,$ between the wall? and the block is 0.5, the magnitude of the frictional force acting on the block is
LCD stands for
Which one of the following ores is obtained by floatation process?
For the dissociation of limestone in the slag zone of the blast furnace, the reaction is
If $x =at + bt^2$ where $x$ is measured in m and t ins, thenthe dimension of (b/a) is
A ring rolls down an inclined plane. The ratio of rotational kinetic energy to translational kinetic energy is
If $\alpha, \beta , \gamma$ are the roots of the equation $x^3 - 3x^2 + 2x - 1 = 0$ then the value of $[(1 - \alpha) (1 -\beta )(1 - \gamma)]$ is
In Lassaigne's test for nitrogen in an organic compound, the blue colouration is due to the formation of
The conjugate acid of $ NH_2^- $ is
The oxidation number of oxygen is -1 in
An electron having spin quantum number, $s = -1/2$ and magnetic quantum number, $m = + 3$ can be present in
A glass hemisphere of radius 0.1 cm and refractive index 1.5 is placed over a spot on a table and the spot is viewed from above. The spot appears to be
In the case of the Bohr atom model, if $E_k$ and $U$ are the kinetic and potential energies of an electron in an orbit then,
The layer in earth's atmosphere which reflects radio waves from the earth thus, helping radio communication is
A particle is moving eastward with velocity $5 \, m \, s^{-1}$ In 10 s the velocity changes to $5\, m\, s^{-1}$ northwards. The average acceleration in this time is
A mass of 0.1 kg is hung at the 20 cm mark from a 1 m rod weighing 0.25 kg pivoted at its centre. The rod will not topple if
The ratio of speed of sound in Hydrogen to that in Oxygen at the same temperature is
Two ions $A^+$ and $B^-$ have radii 104 and 200 pm respectively, in a cubic close packed crystal of compound AB. The co-ordination no. of A is
Two point charges $Q_1 = 2 \mu C$ and $ Q_2 = 1 \mu C$ are placed as shown. The coordinates of the point P are (2 cm, 1 cm). The electric intensity vector at P subtends an angle $\theta$ with the positive X-axis. The value of $\theta$ is given by
The value of $\tan 10^{\circ}\, \tan 20^{\circ} \, \tan 30^{\circ} \, \tan 40^{\circ} \, \tan 50^{\circ}\, \tan 60^{\circ} \tan 70^{\circ} \, \tan 80^{\circ} =$
"Plum pudding" model of an atom was proposed by