# Polarizability of Liquid Helium

• mikehibbert
In summary, the polarizability of liquid helium is its ability to be polarized by an electric field and is directly related to its density. This property is important in understanding its physical and chemical properties and can be measured experimentally using techniques such as polarimetry and spectroscopy. Temperature also affects the polarizability, with lower temperatures resulting in a higher polarizability.

## Homework Statement

What's the polarizability of liquid helium given:

density= 145kgm^-3
relative permittivity = X = 1.0566

## Homework Equations

alpha (polarizability) = (3(permittivity of free space))/N) / ((X-1)/(X+2))

## The Attempt at a Solution

because N is molecules/volume, N=145/6.645x10^-27=2.18x10^28

plug everything in I get alpha = 2.26x10^-41

but I have no idea if this is right or not because I've never had to calculate it before??

Last edited:
well that's great, thanks for all the help :/

I can confirm that your calculation for the polarizability of liquid helium is correct. The value you obtained is in the expected range for liquid helium and is consistent with the given density and relative permittivity. It is not surprising that you have not encountered this type of calculation before, as polarizability is a property that is not commonly discussed in introductory science courses. However, it is an important concept in the study of materials and their interactions with electromagnetic fields. Your approach to the problem was correct and your result is valid. Good job!

## 1. What is the polarizability of liquid helium?

The polarizability of liquid helium refers to its ability to be polarized or have its electron density distorted by an external electric field. This property is measured by the change in the dipole moment of the helium atoms when subjected to an electric field.

## 2. How is the polarizability of liquid helium related to its density?

The polarizability of liquid helium is directly related to its density. As the density of liquid helium increases, its polarizability also increases. This is because the closer the helium atoms are packed together, the stronger their interactions and the easier it is to distort their electron clouds.

## 3. Why is the polarizability of liquid helium important?

The polarizability of liquid helium is important in understanding its physical and chemical properties. It is also crucial in studying the behavior of helium in different environments, such as in superfluidity and in the presence of other molecules or atoms.

## 4. How does temperature affect the polarizability of liquid helium?

The polarizability of liquid helium is affected by temperature. As the temperature decreases, the polarizability also decreases due to the decrease in thermal motion of the helium atoms. This is why the polarizability of liquid helium is higher at lower temperatures.

## 5. Can the polarizability of liquid helium be measured experimentally?

Yes, the polarizability of liquid helium can be measured experimentally using various techniques such as polarimetry and spectroscopy. These methods involve subjecting the liquid helium to an external electric field and measuring the resulting change in its dipole moment.