Question

Block A of weight 100 N rests on a frictionless inclined plane of slope angle 30° (Fig.). A flexible cord attached a to A passes over a frictionless pulley and is connected to block B of weight W. Find the weight W for which the system is in equilibrium.

Answer 1

mg sin 30° = F

\(\frac{1}{2}\)mg = F

F = \(\frac{1}{2}\) × 100 N

= 50 N

For B (at rest), W = F = 50 N.