Radioactivity

Q.

If ${}_{92}{X}^{238}$ undergoes successively 8 $\alpha$ - decays and 6 $\beta$ - decays, then resulting nucleus is

1. ${}_{82}{X}^{206}$

2. ${}_{92}{X}^{206}$

3. ${}_{82}{X}^{214}$

4. ${}_{82}{X}^{210}$

Q.

Unit of the radioactivity is Rutherford. Its value is:

1. $3.7\times {10}^6$ disintegrations/sec

2. $2.7\times {10}^{10}$ disintegrations/sec

3. $3.0\times {10}^{10}$ disintegrations/sec

4. $1.0\times {10}^6$ disintegrations/sec

Q. Why uranium is used over any other radioactive element in a nuclear reaction usually?

Q.

If ${}_{92}{X}^{206}$ undergoes successively 8 $\alpha$ - decays and 6 $\beta$ - decays, then resulting nucleus is

1. ${}_{92}{X}^{206}$

2. ${}_{82}{X}^{210}$

3. ${}_{82}{X}^{206}$

4. ${}_{82}{X}^{214}$

Q.

What is the respective number of $\alpha$ and $\beta$ particles emitted in the following radioactive decay ${}_{90}{X}^{200}{\to }_{80}{Y}^{168}$?

1. 6 and 8

2. 8 and 8

3. 6 and 6

4. 8 and 6

Q.

Which radiation or particle from radioactivity produces maximum biological damage?

1. $\beta -rays$

2. $\gamma -radiations$

3. $\alpha rays$

4. $\Delta rays$

Q. (a) Which radiation or particle from radioactivity produces maximum biological damage?
(b) State three precautions that must be taken while handling a radioactive source. [3 MARKS]

Q. A radioactive nucleus decays from ${}_{92}{X}^{235}$ to ${}_{91}{Y}^{231}$. Which of the following particles are emitted

1. One alpha and one electron
2. Two deuterons and one positron
3. One alpha and one proton
4. One proton and four neutrons