JEE Main 2005 — Modern Physics

A photocell is illuminated by a small bright source placed $1 \mathrm{~m}$ away. When the same source of light is placed $\frac{1}{2} \mathrm{~m}$ away, the number of electrons emitted by photo cathode would

If radius of ${ }_{13}^{27} \mathrm{Al}$ nucleus is estimated to be $3.6$ Fermi then the radius ${ }_{52}^{125} \mathrm{Te}$ nucleus be nearly

In a full wave rectifier circuit operating from $50 \mathrm{~Hz}$ mains frequency, the fundamental frequency in the ripple would be

The diagram shows the energy levels for an electron in a certain atom. Which transition shown represents the emission of a photon with the most energy ? 

The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480 \mathrm{~nm}$ is incident on it. The band gap in (eV) for the semiconductor is

A nuclear transformation is denoted by $X(n, \alpha){ }_3^7 \mathrm{Li}$. Which of the following is the nucleus of element $X$ ?

If the kinetic energy of a free electron doubles. Its deBroglie wavelength changes by the factor