NEET UG 2019 — Modern Physics

The binding energy per nucleon is maximum for

An electron is accelerated through a potential difference of $10,000 V.$ Its de Broglie wavelength is (nearly): $({m}_{e}=9\times 1{0}^{-31} kg)$

The total energy of an electron in an atom in an orbit is $-3.4 eV.$ Its kinetic and potential energies are, respectively,

The work function of a photosensitive material is $4.0 \mathrm{eV}$. This longest wavelength of light that can cause photon emission from the substance is (approximately)

The rate of radioactive disintegration at an instant for a radioactive sample of half life $2.2 \times 10^9 \mathrm{~s}$ is $10^{10} \mathrm{~s}^{-1}$. The number of radioactive atoms in that sample at that instant is

For a $p-$type semiconductor, which of the following statements is true?

$\text{α}$-particle consists of

The radius of the first permitted Bohr orbit for the electron, in a hydrogen atom equals $0.51 Å$ and its ground state energy equals $-13.6 \mathrm{eV}$. If the electron in the hydrogen atom is replaced by muon $\left(\mu^{-1}\right)$ [Charge same as electron and mass $207 \mathrm{~m}_{\mathrm{e}}$ ], the first Bohr radius and ground state energy will be

The circuit diagram shown here corresponds to the logic gate, 

The correct Boolean operation represented by the circuit diagram drawn is, 

An LED is constructed from a p-n junction diode using GaAsP. The energy gap is $1.9 \mathrm{eV}$. The wavelength of the light emitted will be equal to

A proton and an $\alpha$-particle are accelerated from rest to the same energy. The de-Broglie wavelengths $\lambda_p$ and $\lambda_\alpha$ are in the ratio