La 1Fx= 25 cos 20 = 23.49 NFy= 25 sen 20= 8.55 N

Wx= 60 sen 15= 15.52 NWy= 60 cos 15= 57.95 N

Fx= Fx-Wx-Fr=0 -------> por ser vel. cte.23.49-15.52=FrFr=7.97 N

Fy= N+Fy-Wy=0Fn=-Fy+WyFn= -8.55+57.95= 49.4 N

Fr=Mk*NMk= Fr/ NMk=7.97/49.4= .161

b) al subirse solo actuanWx-Fr=mamg=pesom=60/9.81=6.11 kg

N-wy=0N= wyN= 57.95 NFr= N*MkFr= 57.95*.161=9.35N

15.52-9.35=a--------------------6.11

a=1.01 m/s^2