The current gain of a common emitter amplifier is \(69\). If the emitter current is \(7.0\,mA\), collector current is.....\(mA\)

Two light beams fall on a transparent material block at point 1 and 2 with angle \(\theta_1\) and \(\theta_{2^{\prime}}\) respectively, as shown in figure. After refraction, the beams intersect at point 3 which is exactly on the interface at other end of the block. Given : the distance between 1 and 2, \(\mathrm{d}=4 \sqrt{3} \mathrm{~cm}\) and \(\theta_1=\theta_2=\cos ^{-1}\left(\frac{\mathrm{n}_2}{2 \mathrm{n}_1}\right)\), where refractive index of the block \(\mathrm{n}_2\gt\) refractive index of the outside medium \(\mathrm{n}_1\), then the thickness of the block is ________ cm.

In a photoelectric effect experiment the threshold wavelength of incident light is \(380\, nm\), If the wavelength of the incident light is \(260\,nm\), the maximum kinetic energy of emitted electrons will be: .............. \(eV\) Given \(E\) (in \(eV\)) \( = \frac{{1237}}{{\lambda \left( {in\,nm} \right)}}\)

The relation between time \(t\) and distance \(x\) for a moving body is given as \(t=m x^{2}+n x\), where \({m}\) and \({n}\) are constants. The retardation of the motion is - (Where \(v\) stands for velocity)

An electric bulb rated \(50 \mathrm{~W}-200 \mathrm{~V}\) is connected across a \(100 \mathrm{~V}\) supply. The power dissipation of the bulb is _______.

The centre of mass of a solid hemisphere of radius \(8\, cm\) is \(X \,cm\) from the centre of the flat surface. Then value of \(x\) is\(......\)

A capacitor is made of two square plates each of side \(a\) making a very small angle \(\alpha\) between them, as shown in figure. The capacitance will be close to

Five identical cells each of internal resistance \(1\, \Omega\) and \(emf \;5\, {V}\) are connected in series and in parallel with an external resistance \('R'.\) For what value of \('R',\) current in series and parallel combination will remain the same ? (in \(\Omega\))

The half life of a radioactive substance is \(5\) years. After \(x\) years a given sample of the radioactive substance gest reduced to \(6.25 \%\) of its initial value of \(x\) is ...............

A point source of \(100\,W\) emits light with \(5 \%\) efficiency. At a distance of \(5\,m\) from the source, the intensity produced by the electric field component is :

A transistor is used in common-emitter mode in an amplifier circuit. When a signal of \(10\, mV\) is added to the base-emitter voltage, the base current changes by \(10 \mu A\) and the collector current changes by \(1.5 \,mA\). The load resistance is \(5 \,k \Omega\). The voltage gain of the transistor will be

The orbital angular momentum of a satellite is \(L\), when it is revolving in a circular orbit at height \(h\) from earth surface. If the distance of satellite from the earth centre is increased by eight times to its initial value, then the new angular momentum will be \(............\,L\)