After upgrading from Ubuntu 11.10 to 12.04, the wifi on my dell inspiron 14 (N4050) is no longer working.

The Broadcom hardware on my laptop is: Network controller [0280]: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller [14e4:4727] (rev 01).

Anyway to resolve this? I'm a new Ubuntu user.