Create an instance of object in powershell
#in csharp it is: using Microsoft.SharePoint
[void][System.Reflection.Assembly]::LoadWithPartialName("Microsoft.Sharepoint")
#this represents: SPFieldUrlValue field = new SPFieldUrlValue(); in csharp
$field=new-object Microsoft.Sharepoint.SPFieldUrlValue
$field.Url = "https://www.google.com"
$field.Description="My favorite"
#object of Image Type
$image = new-object Microsoft.SharePoint.Publishing.Fields.ImageFieldValue
$image.ImageUrl = "https://server/sitecollection/publishingimages/image1.jpg"
#constructor with parameters
$site = New-Object Microsoft.SharePoint.SPSite($siteUrl)