Heat generation in a disc brake with Comsol. Part 3

[@GhjdbsnTyeuetw]

Thanks for the update on this video

[@MS-Mech_Academy]

Hi sir
I'm getting error while computing.
The error is
THE FOLLOWING FEATURE HAS ENCOUNTERED A PROBLEM:
Feature: Time-Dependent solver 1 ( sol1/t1)
Unknown function or operator
Name : a

[@Simulation_World]

Please check the following:
a) In the Settings window for Analytic, type a in the Function name text field
b)Go to thermal contact 1, In the Pb text field, type -m_car*v(t)*a(t)/8.

[@MS-Mech_Academy]

Yes Its already there but still I m getting error