Question

Two blocks are connected by a string as shown in the diagram. The upper block is hung by another string. A force F applied on the upper string produces an acceleration of $2m/s^2$ in the upward direction in both the blocks. If T and T' be the tensions in the two parts of the string, then

• A. T = 70.8 N and T'= 47.2 N
• B. T = 58.8 N and T'= 47.2 N
• C. T = 70.8 N and T'= 58.8 N
• D. T = 70.8 N and T'= 0

Answer 1

The correct option is A T = 70.8 N and T'= 47.2 N

FBD of mass 2 kg FBD of mass 4kg

T - T' - 20 = 4 ….(i) T' - 40 = 8 …(ii)
By solving (i) and (ii) and T = 72 N and T' =48 N