The decision comes after intense discussions between Kapoor and director Aanand L. Rai of Tanu Weds Manu fame.
Kapoor will now spend time on Jawaharlal Nehru University campus to grasp the conduct and ideology of students there.
"The culture of education at the JNU is radically different from other universities in Delhi and across the country. At JNU students, both male and female, are very politically aware," said a source.
"They talk intelligently on national issues. They dress sensibly, hang out at specific cafes in Delhi, attend seminars and protest actively on national issues. The director wanted Sonam to imbibe all of these traits. And they also speak fluent Hindi," the source added.
When it comes to her spoken Hindi, Kapoor, according to the source, needs to work as hard as Dhanush.
Dhanush is in Mumbai working on the dubbing of the Hindi version of his wife's film 3. He has been working with a Hindi coach, trying to get the language right.
For Kapoor too, it's been decided that her accented Hindi and the haute-couture look just won't do for the film.
At first, the director was not sure if Sonam could carry off the role. But after meeting her, he was convinced.
"I am bowled over by her commitment to get the nuances of the role right. I've found my lady," said Rai.