A body of mass 10 \mathrm{~kg} is moving with an initial speed of 20 \mathrm{~m} / \mathrm{s}. The body stops after 5 \mathrm{~s} due to friction between body and the floor. The value of the coefficient of friction is: (Take acceleration due to gravity g=10 \mathrm{~ms}^{-2} )