An engine approaches a hill with a constant speed. When it is at a distance of \(0.9\, km\), it blows a whistle whose echo is heard by the driver after \(5\, seconds\). If the speed of sound in air is \(330\, m/s\), then the speed of the engine is .... \(m/s\)

There is a uniform electrostatic field in a region. The potential at various points on a small sphere centred at \(P\), in the region, is found to vary between in the limits \(589.0\,V\) to \(589.8\, V\). What is the potential at a point on the sphere whose radius vector makes an angle of \(60^o\) with the direction of the field ?........\(V\)

A plane polarized light is incident on a polariser with its pass axis making angle \(\theta\) with \(x-\) axis, as shown in the figure. At four different values of \(\theta\), \(\theta\, = 8^o, 38^o, 188^o\) and \(218^o\), the observed intensities are same. What is the angle between the direction of polarization and \(x-\) axis.....\(^o\)

In the following circuit, the correct relation between output \(( Y )\) and inputs \(A\) and \(B\) will be

A common transistor radio set requires \(12\,V (D.C.)\) for its operation. The \(D.C.\) source is constructed by using a transformer and a rectifier circuit, which are operated at \(220\, V\) \((A.C.)\) on standard domestic \(A.C.\) supply. The number of turns of secondary coil are \(24,\) then the number of turns of primary are

The mean free path of molecules of a certain gas at \(STP\) is \(1500\,d\), where \(d\) is the diameter of the gas molecules. While maintaining the standard pressure, the mean free path of the molecules at \(373\,K\) is approximately \(..........\,d\)

Magnetic flux (in weber) in a closed circuit of resistance \(20\,\Omega\) varies with time \(t(s)\) as \(\phi=8 t ^{2}-9 t +5\). The magnitude of the induced current at \(t =0.25\,s\) will be \(...mA\)

A geostationary satellite is orbiting around an arbitary planet \(^{\prime} P ^{\prime}\) at a height of \(11 R\) above the surface of \(^{\prime} P ^{\prime} ,\) \(R\) being the radius of \(^{\prime} P .^{\prime}\) The time period of another satellite in hours at a height of \(2R\) from the surface of \(^{\prime} P ^{\prime}\) is \(........\).\(^{\prime} P ^{\prime}\) has the time period of \(24\, hours.\)

When a resistance of \(5\,\Omega\) is shunted with a moving coil galvanometer, it shows a full scale deflection for a current of \(250\,mA\), however when \(1050\,\Omega\) resistance is connected with it in series, it gives full scale deflection for \(25\) volt. The resistance of galvanometer is \(......\,\Omega\).

A projectile is projected with velocity of \(25\, m / s\) at an angle \(\theta\) with the horizontal. After t seconds its inclination with horizontal becomes zero. If \(R\) represents horizontal range of the projectile, the value of \(\theta\) will be : [use \(g =10 m / s ^{2}\) ]

Conductivity of a photodiode starts changing only if the wavelength of incident light is less than \(660 \mathrm{~nm}\). The band gap of photodiode is found to be \(\left(\frac{x}{8}\right) \mathrm{eV}\). The value of \(x\) is _______. (Given, \(\mathrm{h}=6.6 \times 10^{-34} \mathrm{Js}, \mathrm{e}=1.6 \times 10^{-19} \mathrm{C}\) )

Two masses \(M _{1}\) and \(M _{2}\) are tied together at the two ends of a light inextensible string that passes over a frictionless pulley. When the mass \(M _{2}\) is twice that of \(M_{1}\). the acceleration of the system is \(a_{1}\). When the mass \(M_{2}\) is thrice that of \(M_{1}\). The acceleration of The system is \(a_{2}\). The ratio \(\frac{a_{1}}{a_{2}}\) will be.

Boolean relation at the output stage\(-Y\) for the following circuit is