Question

Ma ajutați, va rog?

Answer 1

Vectorial: F+N+G+Ff=ma

Ox:F-Ff=ma

Oy:N-mg=0=>N=mg

Ff=μN=μmg

F=ma+μmg=m(a+μg)=500(4+0,1*10)=500*5=2500 N=2,5 kN

L_Ff=-Ff*d=-μmgd=-0,1*500*10*72=-36000 J=36 kJ