Question 217: Atoms & Nuclei

Question

The radius R of a nucleus of mass number A can be estimated by the formula
R = (1.3 $$ 	imes $$ 10
–15
)A
1/3
m.
It follows that the mass density of a nucleus is of the order of :
(M
prot.
$$ \cong $$ M
neut
$$ \simeq $$ 1.67 $$ 	imes $$ 10
–27
kg)

Accepted Answer

$$R = (1.3 	imes {10^{ - 15}}){A^{{1 \over 3}}}$$
We know, $$m = pV$$
$$ \Rightarrow $$ $$p = {m \over V}$$
$$ \Rightarrow $$ $$p = {{{m_p}A} \over {{4 \over 3}\pi {R^3}}}$$
$$p = {{{m_p}A} \over {{4 \over 3}\pi  	imes {{(1.3 	imes {{10}^{ - 15}})}^3}A}}$$
$$p \approx {10^{17}}kg/m$$

Answer

10
24
kg m
–3

Answer

10
10
kg m
–3

Answer

10
17
kg m
–3

Answer

10
3
kg m
–3

Atoms & Nuclei

The radius R of a nucleus of mass number A can be estimated by the formula R = (1.3 $ \times 10 –15 )A 1/3 m. It follows that the mass density of a nucleus is of the order of : (M prot. \cong M neut \simeq 1.67 \times $ 10 –27 kg)

Choose the correct answer: