# Worksheet: The Atomic Nucleus

Q1:

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

• AGravity
• BWeak nuclear force
• CElectromagnetic force
• DStrong nuclear force
• EElectrostatic force

Q2:

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

Q3:

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.

Q4:

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?

Q5:

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