Police said her friends called out her from outside her room as it was locked from the inside.
They had to go for the examination together and some of her friends looked through the window and found her body hanging.
Immediately police were informed, sources said, adding that police sent the body to nearby Regional Institute of Medical Science and Hospital for post mortem.
Diwankar was a first year student of BE (Electrical), NIT authorities said.
A friend of hers said she was a very good student but was slightly deformed after getting an electric shock some years ago at her home.