The mass of a proton is 1.0073 u and that of the neutron is 1.0087 u (u = atomic mass unit) The binding energy of ${}_{2}H{e}^4$ is (mass of helium nucleus = 4.0015 u)

1. 28.4 MeV

2. 0.061 u

3. 0.0305 J

4. 0.0305 erg

$m_P$ and $m_n$ are masses of proton and neutron respectively. An element of mass m has Z protons and N neutrons, then 

1. $m>Z{m}_p+N{m}_n$

2. $m=Z{m}_p+N{m}_n$

3. $m<Z{m}_p+N{m}_n$

4. m may be greater than, less than or equal to $Z{m}_p+N{m}_n$, depending on the nature of the element.

The nuclei ${}_{6}C_{13}<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>{}_{7}N_{14}$ can be described as [1990]

1. isotones

2. isobars 

3. isotopes of carbon

4. isotopes of nitrogen

If a proton and anti-proton come close to each other and annihilate, how much energy will be released:

1. $1.5\times {10}^{-10}<mspace\; width="1em"></mspace>J$           

2. $3\times {10}^{-10}<mspace\; width="1em"></mspace>J$         

3. $4.5\times {10}^{-10}<mspace\; width="1em"></mspace>J$         

4. None of these

Light energy emitted by stars is due to

1. Breaking of nuclei 

2.Joining of nuclei       

3. Burning of nuclei

4. Reflection of solar light

The constituents of atomic nuclei are believed to be 

1. neutrons and protons

2. protons only

3. electrons and protons

4. electrons, protons and neutrons

If in a nuclear fusion  process, the masses of the fusion nuclei be $m_1<mspace\; width="1em"></mspace>and<mspace\; width="1em"></mspace>m_2$ and the mass of the resultant nucleus be $m_3$, then 

1. $m_3=m_1+m_2$

2. $m_3=\left|m_1-m_2\right|$

3. $m_3<\left(m_1+m_2\right)$ 

4. $m_3>\left(m_1+m_2\right)$

The nuclei of which one of the following pairs of nuclei are isotones? 

1. ${}_{34}S{e}^{74},<mspace\; width="1em"></mspace>{}_{31}G{a}^{71}$ 

2. ${}_{42}M{o}^{92},<mspace\; width="1em"></mspace>{}_{40}Z{r}^{92}$

3. ${}_{38}S{r}^{84},<mspace\; width="1em"></mspace>{}_{38}S{r}^{86}$ 

4. ${}_{20}C{a}^{40},<mspace\; width="1em"></mspace>{}_{16}S_{32}$

The volume occupied by an atom is greater than the volume of the nucleus by factor of about

1. ${10}^{10}$ 

2. ${10}^{15}$ 

3. ${10}^1$ 

4. ${10}^5$