Effect of magnetorheological grease’s viscosity to the torque performance in magnetorheological brake by Abdul Kadir, Khairul Anwar, Nazmi, Nurhazimah, Mohamad, Norzilawati, Shabdin, Muhammad Kashfi, Adiputra, Dimas, Mazlan, Saiful Amri, Nordin, Nur Azmah, Mohd Yusuf, Shahir, Ubaidillah