NEET UG 2006 — Modern Physics

The binding energy of deuteron is 2.2 $\mathrm{MeV}$ and that of ${ }_2^4 \mathrm{He}$ is $28 \mathrm{MeV}$. If two deuterons are fused to form one ${ }_2^4 \mathrm{He}$ then the energy released is:

The radius of germanium (Ge) nuclide is measured to be twice the radius of ${ }_4^9 \mathrm{Be}$. The number of nucleons in Ge are:

A photocell employs photoelectric effect to convert:

The momentum of a photon of energy 1 $\mathrm{MeV}$ in $\mathrm{kg} \mathrm{m} / \mathrm{s}$ will be:

In a radioactive material the activity at time $t_1$ is $R_1$ and at a later time $t_2$, it is $R_2$. If the decay constant of the material is $\lambda$, then:

When photons of energy $h v$ fall on an aluminium plate (of work function $E_0$ ), photoelectrons of maximum kinetic energy $K$ are ejected. If the frequency of radiation is doubled, the maximum kinetic energy of the ejected photoelectrons will be:

A forward biased diode is:

Ionization potential of hydrogen atom is $13.6 \mathrm{eV}$. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy $12.1 \mathrm{eV}$. According to Bohr's theory, the spectral lines emitted by hydrogen will be:

In a discharge tube ionization of enclosed gas is produced due to collisions between:

The following figure shows a logic gate circuit with two inputs $\mathrm{A}$ and $\mathrm{B}$ and the output $\mathrm{C}$. The voltage waveforms of $\mathrm{A}$, $\mathrm{B}$ and $\mathrm{C}$ are as shown below:  The logic circuit gate is: