1997 Toyota Camry silencer/exhaust broke off

Hi,
I was driving my car when it hit suddenly a metal scrap on the road. The scrap got dragged along with the car for some distance when it got disengaged off its own. Since then my car is making a lot of noise(it seems as if I am riding a motorbike). Can you kindly tell me what could be the possible cause of this noise and how much would it cost to get it repaired
thanking you
regards