Physics Test - ...

In the Bohr model of the hydrogen atom, let R, V and E represent the radius of the orbit, the speed of the electron and the total energy of the electron respectively. Which of the following quantity is proportional to the quantum number n?

A long solenoid of cross-sectional radius \(R\) has a thin insulated wire ring tightly put on its winding. One half of the ring has the resistance \(10\) times that of the other half. The magnetic induction produced by the solenoid varies with time as \(B = bt\), whose \(b\) is a constant. Find the magnitude of the electric field strength in the ring.

The value of universal gravitational constant \(\mathrm{G}\) is ________.

For a plane electromagnetic wave, the magnetic field at a point \(x\) and time \(t\) is

\(\vec{B}(x, t)=\left[1.2 \times 10^{-7} \sin \left(0.5 \times 10^3 \mathrm{x}+1.5 \times 10^{11} \mathrm{t}\right) \hat{\mathrm{k}}\right]_{\mathrm{T}}\)

The instantaneous electric field \(\overrightarrow{\mathrm{E}}\) corresponding to \(\mathrm{B}\) is: ( speed of light \(\mathrm{c}=3 \times 10^8 \mathrm{~ms}^{-1}\) )

A dielectric slab of thickness \(1.0\) cm and dielectric constant \(5\) is placed between the plates of a parallel plate capacitor of plate area \(0.01\) m \(^{2}\) and separation \(2.0 \) cm. Calculate the change in capacity on introduction of dielectric.

The wavelength in the bright-line emission spectrum of an element are:

When an alpha particle with mass m, charge 2e enters into a magnetic field B with velocity v perpendicular to the direction of the magnetic field, the radius of the curved path will be ____________.

A satellite of mass \(m\) is placed at a distance \(r\) from the centre of Earth (mass \(M\)). The mechanical energy of the satellite is

Three waves of equal frequency having amplitudes \(10 \mu \mathrm{m}, 4 \mu \mathrm{m}, 7 \mu \mathrm{m}\) arrive at a given point with successive phase difference of \(\frac{\pi}{2}\) radian. The amplitude of the resultant wave is:

When a hydrogen atom is raised from the ground state to an excited state: