Figure shows three blocks of mass m each hanging on a string passing over a pulley. Calculate the tension in the string connecting A to B and B to C?

Explanation

Net force = 2mg -mg = mg
Total mass = m + m + m = 3m
Acceleration , ` a=(mg)/(3m) =(g)/(3)`
Considering block A, `T_1 - mg = ma or T_1 = mg + ma(or)`
`T_1 = mg + m((g)/(3)) (or)`
`T_1 = (4)/(3) mg ` , Considering block C ,
`mg-T_2 = ma (or) T_2 = mg-ma(or)`
`T_2 = mg - (mg)/(3) = (2)/(3) mg ` .