Inside a uniform spherical shell \((a)\) the gravitational field is zero \((b)\) the gravitational potential is zero \((c)\) the gravitational field is same everywhere \((d)\) the gravitation potential is same everywhere \((e)\) all of the above Choose the most appropriate answer from the options given below

The output of the circuit is low (zero) for:

(A) \(\mathrm{X}=0, \mathrm{Y}=0\)
(B) \(X=0, Y=1\)
(C) \(X=1, Y=0\)
(D) \(\mathrm{X}=1, \mathrm{Y}=1\)
Choose the correct answer from the options given below :

The area of cross-section of a railway track is \(0.01\, {m}^{2}\). The temperature variation is \(10^{\circ} {C}\). Coefficient of linear expansion of material of track is \(10^{-5} /{ }^{\circ} {C}\). The energy stored per meter in the track is ...... \({J} / {m} .\) (Young's modulus of material of track is \(10^{11} \,{Nm}^{-2}\) ))

The temperature of an open room of volume \(30\ m^3\) increases from \(17^o C\) to \(27vC\) due to sunshine. The atmospheric pressure in the room remains \(1 \times 10^5\ Pa\). Ifni and nr are the number of molecules in the room before and after heating, then \(n_f-n_i\) will be :

One \(kg\) of water, at \(20\,^oC\), is heated in an electric kettle whose heating element has a mean (temperature averaged) resistance of \(20\, \Omega \). The rms voltage in the mains is \(200\, V\). Ignoring heat loss from the kettle, time taken for water to evaporate fully, is close to.......... \(\min\) [Specific heat of water \(= 4200\, J/kg\, ^oC\)), Latent heat of water \(= 2260\, k\,J/kg\)]

The mass density of a spherical galaxy varies as \(\frac{ K }{ r }\) over a large distance \('r'\) from its centre. In that region, a small star is in a circular orbit of radius \(R\). Then the period of revolution, \(T\) depends on \(R\) as

Identify the semiconductor devices whose characteristics are given below, in the order \((a),(b),(c),(d) \) 

The ranges and heights for two projectiles projected with the same initial velocity at angles \(42^{\circ}\) and \(48^{\circ}\) with the horizontal are \({R}_{1}, {R}_{2}\) and \({H}_{1}\), \({H}_{2}\) respectively. Choose the correct option:

If \(\vec{A}\) and \(\vec{B}\) are two vectors satisfying the relation \(\vec{A} . \vec{B}=[\vec{A} \times \vec{B}]\). Then the value of \([\vec{A}-\vec{B}]\). will be :

In a screw gauge, there are \(100\) divisions on the circular scale and the main scale moves by \(0.5\,mm\) on a complete rotation of the circular scale. The zero of circular scale lies \(6\) divisions below the line of graduation when two studs are brought in contact with each other. When a wire is placed between the studs, \(4\) linear scale divisions are clearly visible while \(46^{\text {th }}\) division the circular scale coincide with the reference line. The diameter of the wire is \(...........\times 10^{-2}\,mm\)

In a linear simple harmonic motion \((SHM)\) \((A)\) Restoring force is directly proportional to the displacement. \((B)\) The acceleration and displacement are opposite in direction. \((C)\) The velocity is maximum at mean position. \((D)\) The acceleration is minimum at extreme points. Choose the correct answer from the options given below :