Gamma Decay

Q.

Which of the following statements are true regarding gamma radiation?

1. Gamma radiations are neutral.

2. Gamma radiations are electromagnetic in nature.

3. Gamma radiations are high energy electrons.

4. Gamma radiations travel with speed of light.

Q.

Are beta rays electromagnetic waves or are beams of particles ? Explain

Q.

When nucleus of an electrically neutral atom undergoes a radioactive decay process, it will remain neutral after the decay, if the process is

1. ${\beta }^{\oplus }$ -decay

2. $\alpha$ -decay

3. $\gamma$ -decay

4. ${\beta }^{\ominus }$ -decay

Q. radiation is electromagnetic in nature.

1. Alpha
2. Beta
3. Gamma

Q.

The diagram given below is showing a radioactive source R in a thick walled container having a narrow opening: The radiations pass through an electric field between the plates C and D.

What is the reason for keeping the source R in a thick lead walled container with a narrow opening?

Q.

What is the speed of $\gamma -rays$? Are they deflected by an electrostatic field?

1. $233m{s}^{-1}$, yes

2. $3\times {10}^{8}m{s}^{-1}$, yes

3. $3\times {10}^{8}m{s}^{-1}$, no

4. $233m{s}^{-1}$, no

Q. An electron beam is moving from left to right of the observer and magnetic field is acting vertically upwards. The direction of force acting on electron is

1. towards the observer
2. away from the observer
3. downwards
4. upwards

Q.

The most penetrating radiation out of the following is :-

1. X-rays

2. $\beta -rays$

3. $\alpha -particles$

4. $\gamma -rays$

Q. An actinium ($\text{Ac}$) sample ($\text{A}:227;\text{Z}:89$) undergoes a series of $\alpha -\beta -\alpha -\gamma$ emissions to attain stability. What is the final daughter nucleus formed in the reaction?

1. $22387\mathrm{Fr}$
2. $23290\mathrm{Th}$
3. $21986\mathrm{Rn}$
4. $21985\mathrm{At}$

Q. The given figure shows a mixed source R of $\alpha -and\beta -particles$ in a thick lead container. The particles pass through a magnetic field in a direction perpendicular to the place of paper inwards as shown by $\times$.
(a) State and show in the diagram how the particles get affected.
(b) Why is the source R kept in a thick lead container? [5 MARKS]

Q.

The radioactive radiations which have the least penetrating power.

1. Neutrino radiation

2. γ-radiation

3. ß-radiation

4. α – radiation

Q. The Fig. 12.4 shows a radioactive source in a thick lead container. The radiations pass through an electric field between the plates A and B. Complete the diagram to show the directions or paths of $\alpha -,\beta -and\gamma -radiations$. [4 MARKS]

Q. What is the kinetic energy of an electron in electronvolts with mass equal to double its rest mass?

1. $511Kev$
2. $250kev$
3. $750Kev$
4. $1500Kev$

Q. A radioactive source emits types of radiations. Name the radiation which has the highest ionizing power.

1. $\alpha$
2. $\gamma$
3. $\beta$
4. none of these

Q. Consider $\alpha -particles,\beta -particles$, and $\gamma -rays$, each having an energy of 0.5 MeV. In increasing order of penetrating powers, the radiations are

1. $\alpha ,\gamma ,\beta$
2. $\beta ,\gamma ,\alpha$
3. $\alpha ,\beta ,\gamma$
4. $\gamma ,\beta ,\alpha$

Q. A mixture of radioactive substances gives off three types of radiations.
(a) Name these three types of radiations.
(b) Name the type of radiation consisting of the same kind of particles as cathode rays.
(c) One of these radiations is similar to X-rays. Name the radiation.
(d) When the particle referred to in (c) becomes neutral, it is found to be the atom of a rare gas. Name this rare gas.
[5 MARKS]

Q.

Find the atomic number of $X_3$ in the following nuclear reaction,

$21485X\to X_1+\beta \to X_2+\gamma \to X_3+\alpha$

1. $82$
2. $86$
3. $84$
4. $80$

Q. In a hydrogen atom, the electron makes a transition from $n=2$ to $n=1$. The magnetic field produced by the circulating electron at the nucleus

1. Decreases 16 times
2. Decreases 4 times
3. Increases 32 times
4. Increases 4 times

Q. One of the radioactive radiations is similar to X-rays in nature. Name it and give its properties. [5 MARKS]

Q. Gamma emission occurs when the atomic nucleus is in an excited state.

1. True
2. False

Q. Gamma rays have a very high penetrating power.

1. True
2. False

Q. Gamma rays are the most energetic and fatal form of radiation.

1. True
2. False

Q. When the nucleus of an electrically neutral atom undergoes a radioactive decay process, it will remain neutral after the decay if the process is

1. an $\alpha$ decay
2. a $\gamma$ decay
3. a ${\beta }^{-}$ decay
4. a $K$ -capture process

Q.

Which of the following radioactive radiations is similar to X-rays in nature?

1. $\gamma rays$

2. Infrared rays

3. $\alpha rays$

4. $\beta rays$

Q. Why can gamma rays travel through the air for a long distance?

1. They have very high kinetic energy.

2. They have a smaller rate of collision with the atoms (or molecules) of the medium.

3. They possess more mass than an alpha particle.

4. They have less ionizing power but more penetrating power.

Q. In which of the following decays the atomic number decreases?

1. ${\beta }^{+}$-decay
2. $bet{a}^{-}$-decay
3. $\alpha$- decay
4. $\gamma$-decay

Q. Gamma emission affects the mass number and the atomic number of an atom.

1. True
2. False

Q. $\gamma$-emission results in a change in either the atomic number or the mass number of the parent nucleus.

1. False
2. True

Q. A radioactive source emits three types of radiations.Name the radiation which travels with the speed of light.

1. None of these
   
2. Beta
3. Gamma
   
4. Alpha