Question

Considere os blocos A e B dispostos como mostra a figura. As massas dos blocos A e B são, respectivamente, 30 kg e 70 kg. A polia e o fio são ideais. Considere g = 10 m/s². *
1 ponto
Desprezando qualquer tipo de atrito, determine a força de tração que traciona o fio.

Answer 1

$\displaystyle \underline{\text{bloco B}} :\\\\ \text{F}_\text r =\text T \to 70.\text a =\text T\\\\\\\ \underline{\text{bloco A}}:\\\\ \text{F}_\text r=\text P_\text A-\text T \to 30.\text a=30.10-\text T \\\\ (\text{por{\'e}m T = 70a.})\\\\ \therefore \\\\ 30\text a =300-70\text a\\\\ 100\text a=300 \\\\ \text a = 3\ \text{m/s}^2\\\\ \underline{\text{Portanto}}: \\\\ \text T = 70.3 \\\\ \huge\boxed{\text T=210 \ \text N\ }\checkmakr$