I have upgraded my Nexus 4 to Android 5.0 and now the phone bips on receiving a call but is not using the ring tone that i have chosen. it is like it was stuck in silent mode but hen i cant find the place to take it out of this mode
Set the Priority mode to All. This can be done via the Volume Up button:
"For fewer disruptions, turn on Priority mode via your device's volume button so only certain people and notifications get through. Or schedule recurring downtime like 10pm to 8am when only Priority notifications can get through."
The Priority notifications offers three modes namely - None, Priority, and All. The Priority mode will only allow a few set of notifications to go through and users will see a Star mark in the status bar when in this mode. Meanwhile, the None mode will allow the phone to receive all notifications but will not alert the user. Notably, the None mode in Priority notifications even limits set alarm functionality.
Motorola has shared a YouTube video to explain the new Priority notifications on the Moto X running the new Android 5.0 Lollipop.