MCA Entrance Previous Year Question Bank

A molecule makes a transition between the ground state and an excited state having a lifetime of 10⁻³ s. the width of the associated spectral line is:

When a hydrogen atom emits a photon of energy 12.1 eV, its orbital angular momentum changes by:

The energy of a photon of sodium light of λ = 5890 Å equals the bandgap of a semiconducting material. The minimum energy required to create an electron hole pair is:

The residue of f(z) = ∫${}_C$ $\frac{(2z-3)dz}{z(z-1)}$ where C is the circle |z| = 2 at the pole z = 0 is:

The collector leakage current in a transistor ($\beta =120$) is 300 $\mu$A in CE configuration. If the transistor is now connected in CB arrangement, the new leakage current will be:

A transistor in CE configuration used as phase shift oscillator in which $R_1=R_2=R_3=R=10$ K$\Omega$, $C_1=C_2=C_3=C=0.01$ $\mu$F and $R_1=10$ K$\Omega$. The frequency of oscillation will be:

In a transistor (β = 45), the voltage across 5 kΩ load resistance in collector circuit is 5V. the base current is:

Two beams of light having intensities I and 4I interfere to produce a fringe pattern on a screen. The phase difference between the beams is π/2 at a point A and at a point B. Then the difference between resultant intensities at A and B is:

What will be the thickness of a quarter wave plate when the wavelength of light is 5890 Å and ${\mu }_G=1.553$, ${\mu }_D=1.544$?

The state of polarization of the wave $\vec{E}$ (z, t) = $E_0\left[\sin (kz-\omega t)-j\cos (kz-\omega t)\right]$ is: