[tex]lucrumecanic = aria \: hasurata[/tex]
[tex]lcrumecanic = lungime \times latime[/tex]
[tex]lucrumecanic = (5 - 2) \times 10[/tex]
[tex]lucrumecanic = 30jouli[/tex]
3.
L=F×d×cos alfa
L=20×10×radical din 3 pe 2
L=200×0,15=30 Jouli
