The magnetic flux through a coil perpendicular to its plane is varying according to the relation \(\phi=\) \(\left(5 t^{3}+4 t^2+2 t-5\right) \; Weber\). If the resistant of the coil is \(5 \; ohm\), then the induced current through the coil at \(t =2 \; sec\) will be \(....\,A\)

In parallax method for the determination of focal length of a concave mirror, the object should always be placed :

A radioactive element \({ }_{92}^{242} X\) emits two \(\alpha\)-particles, one electron and two positrons. The product nucleus is represented by \({ }_{ P }^{234} Y\). The value of \(P\) is \(..................\)

\(X\) different wavelengths may be observed in the spectrum from a hydrogen sample if the atoms are exited to states with principal quantum number \({n}=6\) ? The value of \({X}\) is ..... .

If \(\mu_0\) and \(\varepsilon_0\) are the permeability and permittivity of free space, respectively, then the dimension of \(\left(\frac{1}{\mu_0 \varepsilon_0}\right)\) is :

Taking the wavelength of first Balmer line in hydrogen spectrum (\( n = 3\) to \(n = 2\) ) as \(660\,nm ,\) the wavelength of the \(2^{nd}\) Balmer line ( \(n =4\) to \(n = 2\) ) will be....\(nm\)

Two particles \(\mathrm{X}\) and \(\mathrm{Y}\) having equal charges are being accelerated through the same potential difference. Thereafter they enter normally in a region of uniform magnetic field and describes circular paths of radius \(R_1\) and \(R_2\) respectively. The mass ratio of \(\mathrm{X}\) and \(\mathrm{Y}\) is _______.

In the given circuit diagram, the currents, \({I_1} =  - \,0.3\,A,\,{I_4} = 0.8\,A\) and \({I_5} = 0.4\,A,\) are flowing as shown. The currents \(I_2,\,I_3\) and \(I_6,\) respectively are

Which level of the single ionized carbon has the same energy as the ground state energy of hydrogen atom ?

A parallel plate capacitor has plate area \(100\, m ^{2}\) and plate separation of \(10\, m\). The space between the plates is filled up to a thickness \(5\, m\) with a material of dielectric constant of \(10 .\) The resultant capacitance of the system is \('x'\) \(pF\). The value of \(\varepsilon_{0}=8.85 \times 10^{-12} F \cdot m ^{-1}\) The value of \('x'\) to the nearest integer is............

An inductor coil stores \(64\, {J}\) of magnetic field energy and dissipates energy at the rate of \(640\, {W}\) when a current of \(8\, {A}\) is passed through it. If this coil is joined across an ideal battery, find the time constant of the circuit in seconds

Given below are two statements: one is labelled as Assertion \(A\) and the other is labelled as Reason \(R\) Assertion \(A:\) Diffusion current in a \(p-n\) junction is greater than the drift current in magnitude if the junction is forward biased. Reason \(R:\) Diffusion current in a \(p-n\) junction is from the \(n\)-side to the \(p\)-side if the junction is forward biased. In the light of the above statements, choose the most appropriate answer from the options given below