A nucleus of uranium -235 absorbs a slow neutron and undergoes nuclear fission according to the reaction: ${ }_{92}^{235} U+{ }_0^1 n \rightarrow{ }_{56}^{141} B a+{ }_{36}^{92} K r+3{ }_0^1 n+Q$
If the average energy released per fission is 202 MeV , the energy released when 2.35 g of $U^{235}$ undergoes complete fission is approximately;
[Given $1 \mathrm{eV}=1.6 \times 10^{-19} \mathrm{~J}$, Avogadro number $=6.02 \times 10^{23}$ ]
$1.945 \times 10^{10} J$
$19.45 \times 10^{11} J$
$1.945 \times 10^{11} J$
$19.45 \times 10^{10} \mathrm{~J}$
Two bodies of specific heats $C_1$ and $C_2$, having the same heat capacities are combined to form a single composite body. The specific heat capacity of the composite body is
$C_1-C_2$
$\frac{2 C_1 C_2}{C_1+C_2}$
$C_1+C_2$
$\frac{2 C_2}{C_1+C_2}$
In a PN junction diode, the forward bias is increased gradually from 0 Volt to 1 Volt. Which of the following statements is correct?
A. The depletion width increases, and barrier potential increases
B. The depletion width decreases, but the electric field inside the junction increases
C. The depletion width remains unchanged, but current increases
D. The depletion width decreases and barrier potential decreases
B
A
D
C

Two charges 1 C and 2 C are placed at coordinates $(0,3)$ and $(4,3)$ respectively in an XY plane. What is the work done to put a 30 C charge at the origin of the coordinate system?
$1.98 \times 10^9 \mathrm{~J}$
$198 \times 10^9 J$
$19.8 \times 10^9 J$
$3.98 \times 10^9 \mathrm{~J}$
COMEDK Papers
All year-wise previous year question papers