Ping a list of hostnames and do reverse dns lookup

Welcome!

Take a look at Test-Connection and Resolve-DNSName. Resolve-DNSName can do reverse lookups.

Docs:

Something like this should do the trick, but you may need to slightly tweak for your needs.

$Connection = Test-Connection -TargetName WRKSTN101.mydomain.com -Ping -Count 1
$DNS = Resolve-DNSName -Name $Connection.DisplayAddress
#$DNS will be a object that has multiple properties, probably the one you care about is the NameHost property
$DNS.NameHost