A block of mass 5kg is (i) pushed in case (A) and (ii) pulled in...

For Block A:

$N = mg + Fsin 30 °$
$= 5 \times 10 + 20 \times \dfrac{1}{2}$
$= 60N$
${f}_{r} = \left(0.2\right)\left(60\right) = 12N$
Fcos 30 ° – {f}_{r} = ma$<br />$20\dfrac{\sqrt{3}}{2} - 12 = 5 \times a$<br />$⇒ {a}_{A} = \dfrac{10\sqrt{3} - 12}{5}&hellip;&hellip;(i)<br />For Block B:<br /><img src="https://cdn-question-pool.Quantrex.app/pyq/jee_main/61ab6514-4877-450e-9a19-78a412642c14-image.png" style="width: 300px; height: 189px;" /><br />Fsin 30 ° + N = mg
$N = 5 \times 10 – 20 \times \left(\dfrac{1}{2}\right)$
$= 40N$
${f}_{r} = 0.2 \times 40 = 8N$
Fcos30 ° – {f}_{r} = ma$<br />$20\left(\dfrac{\sqrt{3}}{2}\right) - 8 = 5 \times a$<br />$⇒ {a}_{B} = \dfrac{10\sqrt{3} - 8}{5}$<br />${a}_{B} - {a}_{A} = \dfrac{4}{5} = 0.8m / {s}^{2}