Answer 1

Mass of each block is 1 kg, \[\sin \theta_1 = \frac{4}{5}\]
\[\sin \theta_2 = \frac{3}{5}\]
The free-body diagrams for both the boxes are shown below:

mgsinθ₁ − T = ma    ...(i)
 T − mgsinθ₂ = ma    ...(ii)
Adding equations (i) and (ii),we get:
mg(sinθ₁ − sinθ₂) = 2ma 
⇒ 2a = g (sinθ₁ − sinθ₂)
\[\Rightarrow a = \frac{g}{5} \times \frac{1}{2}\]
\[ = \frac{g}{10}\]