For the given circuit the current \(i\) through the battery when the key in closed and the steady state has been reached is .....\(A\)

For a constant collector-emitter voltage of \(8\,V\), the collector current of a transistor reached to the value of \(6\,mA\) from \(4\,mA\), whereas base current changed from \(20\,\mu A\) to \(25\,\mu\,A\) value. If transistor is in active state, small signal current gain (current amplification factor) will be.

A block of mass 25 kg is pulled along a horizontal surface by a force at an angle \(45^{\circ}\) with the horizontal. The friction coefficient between the block and the surface is 0.25. The displacement of 5 m of the block is:

A light whose electric field vectors are completely removed by using a good Polaroid, allowed to incident on the surface of the prism at Brewster's angle. Choose the most suitable option for the phenomenon related to the prism.

A coin is placed on a disc. The coefficient of friction between the coin and the disc is \(\mu\). If the distance of the coin from the center of the disc is \(r\), the maximum angular velocity which can be given to the disc, so that the coin does not slip away, is _______.

As per the given circuit, the value of current through the battery will be \(\dots \; A\).

Two rods \(A\) and \(B\) of identical dimensions are at temperature \(30\,^oC\). If a heated upto \(180\,^oC\) and \(B\) upto \(T\,^oC\), then the new lengths are the same. If the ratio of the coefficients of linear expansion of \(A\) and \(B\) is \(4:3\), then the value of \(T\) is........\(^oC\)

Two steel wires having same length are suspended from a ceiling under the same load. If the ratio of their energy stored per unit volume is \(1: 4,\) the ratio of their diameters is

In the given figure, a body of mass \(M\) is held between two massless springs, on a smooth inclined plane. The free ends of the springs are attached to firm supports. If each spring has spring constant \(k,\) the frequency of oscillation of given body is :

The identical spheres each of mass \(2 \mathrm{M}\) are placed at the corners of a right angled triangle with mutually perpendicular sides equal to \(4 \mathrm{~m}\) each. Taking point of intersection of these two sides as origin, the magnitude of position vector of the centre of mass of the system is \(\frac{4 \sqrt{2}}{x}\), where the value of \(x\) is _______.

Time period of a simple pendulum is \(T\). The time taken to complete \(5 / 8\) oscillations starting from mean position is \(\frac{\alpha}{\beta} T\). The value of \(\alpha\) is ..... .

If the radius of earth shrinks by \(2 \%\) while its mass remains same. The acceleration due to gravity on the earth's surface will approximately.

A source of sound \(A\) emitting waves of frequency \(1800\,Hz\) is falling towards ground with a terminal speed \(v.\) The observer \(B\) on the ground directly beneath the source receives waves of frequency \(2150\,Hz.\) The source \(A\) receives waves, reflected from ground of frequency nearly ..... \(Hz\) (Speed of sound \(= 343\,m/s\) )