Using powershell make the SharePoint choice field default value to null

In this blog we will be seeing how to make the choice field default value to null in sharepoint using powershell

I have a custom list "cl1" which has a choice field "Choice". The values for the choice field are "A", "B","C" & "D".
If you create a Choice column through UI the default value will be selected as "A".

In this we will be seeing how to change the choice field default value to null using powershell

$site = Get-SPSite "http://serverName:1111/sites/sample "
$web=$site.Rootweb
$list = $web.Lists.TryGetList("cl1")
$field = $list.Fields["Choice"]
$field.DefaultValue = $null
$field.Update() 
$list.Update()