Using equipartition of energy, the specific heat (in \(J\, kg^{-1}\, K^{-1}\) ) of aluminium at room temperature can be estimated to be ( atomic weight of aluminium \(= 27\))

Two simple harmonic motions are represented by the equations \({x}_{1}=5 \sin \left(2 \pi {t}+\frac{\pi}{4}\right)\) and \({x}_{2}=5 \sqrt{2}(\sin 2 \pi {t}+\cos 2 \pi {t})\) The amplitude of second motion is ....... times the amplitude in first motion.

The length of a seconds pendulum at a height \(h=2 R\) from earth surface will be _______. (Given: \(R =\) Radius of earth and acceleration due to gravity at the surface of earth \(g =\pi^{2}\,m / s ^{-2}\) )

When a certain photosensitive surface is illuminated with monochromatic light of frequency \(v\) , the stopping potential for the photo current is \(-V_0/2.\) When the surface is illuminated by monochromatic light of frequency \(v/2,\) the stopping potential is \(-V_0.\) The threshold frequency for photoelectric emission is

The critical angle of a medium for a specific wavelength, if the medium has relative permittivity \(3\) and relative permeability \(\frac{4}{3}\) for this wavelength, will be.....\(^o\)

In a metre-bridge when a resistance in the left gap is \(2\ \Omega\) and unknown resistance in the right gap, the balance length is found to be \(40\ \mathrm{cm}\). On shunting the unknown resistance with \(2\ \Omega\), the balance length changes by _______.

A \(70\, kg\) man leaps vertically into the air from a crouching position. To take the leap the man pushes the ground with a constant force \(F\) to raise himself The center of gravity rises by \(0.5\, m\) before he leaps. After the leap the \(c.g.\) rises by another \(1\, m\). The maximum power delivered by the muscles is : (Take \(g\, = 10\, ms^{-2}\))

An object viewed from a near point distance of \(25\, {cm}\), using a microscopic lens with magnification \('6',\) gives an unresolved image. A resolved image is observed at infinite distance with a total magnification double the earlier using an eyepiece along with the given lens and a tube of length \(0.6\, {m}\), if the focal length of the eyepiece is euqal to \(.... \,{cm} .\)

A capacitor of capacitance \(100\  \mu \mathrm{F}\) is charged to a potential of \(12  \mathrm{~V}\) and connected to a \(6.4 \ \mathrm{mH}\) inductor to produce oscillations. The maximum current in the circuit would be :

In a meter bridge experiment resistances are connected as shown in the figure. Initially resistance \(P\, = 4\,\Omega \) and the neutral point \(N\) is at \(60\,cm\) from \(A\). Now an unknown resistance \(R\) is connected in series to \(P\) and the new position of the neutral point is at \(80\,cm\) from \(A\) . The value of unknown resistance \(R\) is