Which one of the following statements about uranium is correct?

If $200 \text{ MeV}$ of energy is released in the fission of one nucleus of ${ }_{92}^{236} U$, the number of nuclei that must undergo fission to release an energy of $1000 \text{ J}$ is

In the Sun,the important source of energy is

According to classical physics,$10^{-15} \ m$ is the distance of closest approach $(d_c)$ for fusion to occur between two protons. $A$ more accurate quantum approach states that $d_c = \frac{\lambda_p}{\sqrt{2}}$,where $\lambda_p$ is the de Broglie wavelength of a proton when they were far apart. Using this quantum approach,find the equation for the temperature $(T_c)$ at the center of a star. [Given: $M_p$ is the mass of the proton,$k$ is the Boltzmann constant,$e$ is the elementary charge]

Which of the following are suitable for the fusion process?

The average energy of a neutron produced in the fission of ${ }_{92}^{235} U$ is