# Worksheet: The Atomic Nucleus

In this worksheet, we will practice describing the structure of atomic nuclei and linking variations in nuclear stability to interactions between nucleons.

Q1:

The radius of the nucleus of is approximately 4.8 pm. What is the average density of the nucleus to one significant figure, assuming it is spherical in shape?

• A g/cm3
• B g/cm3
• C g/cm3
• D g/cm3
• E g/cm3

Q2:

What is the main attractive force between particles in the nucleus of an atom?

• AGravity
• BStrong nuclear force
• CWeak nuclear force
• DElectrostatic force
• EElectromagnetic force

Q3:

The radius of an atomic nucleus, , can be estimated using the equation , where and is the number of nucleons in the nucleus. Assuming the nucleus is spherical in shape, find an expression for the approximate average nuclear density in atomic mass units per unit volume.

• A
• B
• C
• D
• E

Q4:

A neutron star has a mass of 2.40 solar masses and a diameter of 26.0 km. A solar mass is kg.

Calculate the density of the neutron star, assuming it is spherical.

• A kg/m3
• B kg/m3
• C kg/m3
• D kg/m3
• E kg/m3

A uranium-235 nucleus has a diameter of 15.0 fm. Calculate the density of this nucleus as a percentage of the density of the neutron star.

Q5:

A neutron star has a mass of 1.97 solar masses and a diameter of 13.0 km. A solar mass is kg.

What is the density of the neutron star to two significant figures, assuming it is spherical?

• A kg/m3
• B kg/m3
• C kg/m3
• D kg/m3
• E kg/m3

A hydrogen nucleus has a diameter of 1.75 fm. What is the density of this nucleus as a percentage of the density of the neutron star, to two significant figures?