How do I find the thermal energy created by a book's motion?

the book's mass is .78 kg and it slides across a table with an initial speed of 1.2m/s. Friction causes the book to slow to a stop. How much thermal energy was created by the book's motion?How do I find the thermal energy created by a book's motion?Kinetic energy = 1/2 mv虏

That converts to thermal energy like BTUs, watts, or joules but I don't know the conversion.How do I find the thermal energy created by a book's motion?WHile a small fraction of the book's kinetic energy may have gone into sound, almost all of it went to heat.