Răspuns:
Presupunem ca M urca,m trage M :
M*a = T - Gt - Ff
m*a = Gm - T
Gt = Mgsin de alfa = 10 * sqrt(2) =14.1 N
Ff = miu * m*g*cos de alfa = 10 sqrt(2) / 2 sqrt(2) = 5 N
(M+m)*a = Gm - Gt - Ff => 2 * 2 + 2*m = 10m - 14.1 - 5
8m = 14.1+5+4 => m = 23.1/8 ~= 2.9 =~ 3kg