It is faster to take the train, and it is only slightly more expensive than the bus. There are two direct National Express bus services a day to Cambridge from Surrey Street bus station. Alternatively, you can catch one of eight buses per day that go to Stansted airport, and then transfer to a Cambridge-bound coach. The journey takes between 2 hours 10 minutes and 4 hours 35 minutes. The fastest bus departs from Surrey Street at 17:45.The first coach leaves at 00:15 and the last one is at 22:15. A single ticket costs 11.60 GBP and a return costs 15-18 GBP.
After booking online, you will be issued with an e-ticket, which you need to print out and take with you, or an m-ticket, which is sent to your mobile phone. Otherwise you can get at ticket at the bus station. Buses from Norwich to Cambridge can be very crowded at times and there is no guarantee of a place unless you book in advance.

There are two trains per hour to Cambridge, one is direct. The journey time is around 1 hour 20 minutes, and it is slightly faster to take the non-direct train and change at Ely. A single journey is 12.90 GBP or an off peak return is 18.40 GBP.
The UK train ticketing system is notoriously complicated. It is usually cheaper to buy your tickets up to 6pm on the day before you travel than on the day. And fares are more expensive if you travel before 09:30.
On arrival in Cambridge, it is a 15-minute walk to the town centre, or you can catch a taxi outside the station for around 5 GBP. There is also a bus that runs about every 10 minutes.
To walk, exit the station and continue along Station Road, which is directly in front of you. At the T-junction, turn right onto Hills Road, which takes you towards the city centre.
If you are looking for a deal on accomodation on arrival in Cambridge why not check out some hotels deals:
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