Nucleus: Common Terms

Q.

A particle of mass $2mg$ moves with constant speed and is found to pass two points $5.0m$ apart in a time interval of $5ms$. Find the kinetic energy of the particle

1. $1J$

2. $2J$

3. $3J$

4. $4J$

Q.

Name the scientists who were responsible for the following scientific development:
The discovery of the existence of neutrons.

Q. The $\alpha$ -particle is the nucleus of --------- atom .

1. Neon
2. Hydrogen
3. Helium
4. Deuterium

Q.

The mass number of a nucleus is

1. Always less than its atomic number

2. Always more than its atomic number

3. Always equal to its atomic number

4. Sometimes more than and sometimes equal to its atomic number

Q.

Which of the given relations about the above elements are correct.
I) ${}^{12}C$
II) ${}^{14}C$
III) ${}^{14}N$
IV) ${}^{16}O$

1. I and II are isotopes

2. II and III are isobars

3. II and IV are isotones

4. III and IV are isobars

Q.

The distance of the closest approach of an alpha particle fired at a nucleus with kinetic energy K is $r_0$. The distance of the closest approach when the alpha particle is fired at the same nucleus with kinetic energy 2K will be

1. $2r_0$

2. $4r_0$

3. $\frac{r_0}{2}$

4. $\frac{r_0}{4}$

Q.

Nuclei with same number of protons but different number of neutrons are called ___.

Nuclei with same number of neutrons but different atomic number are called ___.

Nuclei with same mass number are called ___.

Q. Atomic number of a nucleus is Z and atomic mass is M. The number of neutron is

1. M-Z
2. M
3. Z
4. M+Z

Q.

The distance of the closest approach of an alpha particle fired at a nucleus with kinetic energy K is $r_0$. The distance of the closest approach when the alpha particle is fired at the same nucleus with kinetic energy 2K will be

1. $2r_0$

2. $4r_0$

3. $\frac{r_0}{2}$

4. $\frac{r_0}{4}$

Q.

The value of A for a neutral atom is 25 and Z is 12; find the number of protons, neutrons and electrons in the atom.

1. 12, 25 and 12 respectively

2. 25, 12 and 25 respectively.

3. 12, 13 and 12 respectively

4. 12, 25 and 25 respectively