Nuclear Fission

Q.

An engine develops 10 kW of power. How much time will it take to lift a mass of 200 kg to a height of 40 m. ($g=10m/se{c}^2$)

1. 4 sec

2. 5 sec

3. 8 sec

4. 10 sec

Q. uranium 238 nucleus initially at rest emits an Alpha particle with energy E the recoil speed of residual nucleus thorium 234 is

Q.

What is the half-life decay formula ?

Q.

The radioactive decay of uranium into thorium is represented by the equation
${}_{92}^{238}U\to {}_{90}^{234}Th+x$
What is x?

1. an electron

2. a proton

3. an alpha particle

4. a neutron

Q.

In a fission reaction
${}_{92}^{238}U\to {}^{117}X{+}^{117}Y+n+n$
the binding energy per nucleon of X and Y is 8.5 MeV whereas that of ${}^{236}U$ is 7.6 MeV. The total energy liberated will be about

1. 200 keV

2. 2 Mev

3. 200 MeV

4. 2000 MeV

Q. Suppose the charge of a proton and an electron differ slightly. One of them is $-e$, the other is $(e+\Delta e)$. If the resultant of electrostatic force and gravitational force between two hydrogen atoms placed at a distance $d$ (much greater than atomic size) apart is zero, then $\Delta e$ is of the order of [Given mass of hydrogen $m_h=1.67\times {10}^{-27}kg$]
[NEET- 2017]

1. ${10}^{-20}C$
2. ${10}^{-37}C$
3. ${10}^{-23}C$
4. ${10}^{-47}C$

Q. When ${}_{92}{U}^{235}$ undergoes fission. 0.1% of its original mass is changed into energy. How much energy is released if 1 kg of ${}_{92}{U}^{235}$ undergoes fission

1. $9\times {10}^{10}J$
   
2. $9\times {10}^{11}J$
   
3. $9\times {10}^{12}J$
   
4. $9\times {10}^{13}J$

Q. On the bombardment of a neutron with Boron. $\alpha$-particle is emitted and product nuclei formed is

1. ${}_6{C}^{12}$
2. ${}_{3}L{i}^6$
3. ${}_{3}L{i}^7$
   
4. ${}_{4}B{e}^9$

Q. A nuclear fission is given below
$A^{240}\to B^{100}+C^{140}+Q\left(\text{energy}\right)$.
Let binding energy per nucleon of nuclei $A,B$ and $C$ be $7.6\text{MeV},8.1\text{MeV}$ and $8.1\text{MeV}$ respectively. Value of $Q$ is : (Approximately)

1. $20\text{MeV}$
2. $220\text{MeV}$
3. $120\text{MeV}$
4. $240\text{MeV}$

Q.

Who conducted the first controlled fission reaction?

1. Fermi

2. Cavendish

3. Otto Hahn

4. Hans Bethe

Q. $\beta -$ decay of a nucleus is an example of -

1. Electromagnetic Force
2. Gravitational force
3. Weak Nuclear Force
4. Strong Nuclear Force

Q. The number of neutrons released when ${}_{92}^{235}U$ undergoes fission by absorbing ${}_0^{1}n$ and $\left({}_{56}^{144}Ba{+}_{36}^{89}Kr\right)$ are formed

1. $0$
2. $1$
3. $2$
4. $3$

Q. A nucleus of mass number 220 initially at rest emits an alpha particle. If the $Q$ value of the reaction is $5.5MeV$, then the kinetic energy of the alpha particle is

1. $6.5MeV$
2. $5.5MeV$
3. $5.4MeV$
4. $2.0MeV$

Q. A hypothetical nuclear fission takes place as following:
${}_{92}^{236}X{\to }_{56}^{140}Y{+}_{36}^{94}Y+netron/s$
How many neutrons will get emitted in the process?

1. 1
2. 2
3. 3
4. 4

Q. Can we convert uranium to gold by nuclear reaction

Q. ${}_{26}^{56}Fe⟶2{(}_{13}^{28}Al)m_{Fe}=55.93494m_{Al}=27.98191$
Find Q value of reaction. Is fission energetically possible?

1. -27 MeV, Yes
2. 27 MeV, No
3. 15 MeV, Yes
4. -15 MeV, No

Q.

Find the energy liberated in the reaction: ${}^{223}Ra{\to }^{209}Pb{+}^{14}C$
The atomic masses needed are as follows:
$\underset{223.018u}{{}^{223}Ra}$ $\underset{208.981u}{{}^{209}Pb}$ $\underset{14.003u}{{}^{14}C}$

1. 31.654 MeV

2. 32.654 MeV

3. 30.054 MeV

4. None of these

Q. The number of neutrons released when ${}_{92}^{235}U$ undergoes fission by absorbing ${}_0^{1}n$ and $\left({}_{56}^{144}Ba{+}_{36}^{89}Kr\right)$ are formed

1. $0$
2. $1$
3. $2$
4. $3$

Q. The binding energy per nucleon of ${}_1^{2}H$ and ${}_2^{4}He$ are $1.1MeV$ and $7.0MeV$ respectively. Energy released in the process ${}_1^{2}H{+}_1^{2}H{\to }_2^{4}He$ is

1. $23.6MeV$
2. $25.2MeV$
3. $16.6MeV$
4. $13.6MeV$