Question

In the adjacent Figure, masses of A, B and C are 1 kg, 3 kg and 2 kg, respectively. Find (a) the acceleration of the system and (b) tension in the string. Neglect friction (g = 10m/s²)

Answer 1

Draw the FBD of each block and apply Newton’s second law along the incline plane for each block.

(a) In this case, the net pulling force

Therefore, the total mass being pulled = 1 + 3 + 2 = 6 kg

∴ Acceleration of the system a = 21.17/6 = 4.1 m/s²

(b) For the tension in the string between A and B.

(b) For the tension in the string between B and C. FBD of C, T₂ - m_cgsin30° = m_ca