Question

me ajudemm, preciso dessa lição urgente

Answer 1

$F = (m_A+m_B)a\\30 = (10+5)a\\15a = 30\\a = \frac{30}{15}\\\boxed{a=2,0m/s^2}\\\\F_{AB}= m_Ba\\F_{AB}=5 \cdot 2\\\boxed{F_{AB}=10N}\\\\F_{R(A)}=F - F_{AB}\\F_{R(A)}=30-10\\\boxed{F_{R(A)}=20N}$