Three identical blocks of masses \[m=2\] kg are drawn by a force \[F=10.2\] N with an acceleration of \[0.6\,\,m{{s}^{-2}}\] on a frictionless surface, then what is the tension (in N) in the string between the blocks B and C?
AIEEE Solved Paper-2002
A)\[9.2\]
B) \[7.8\]
C) 4
D) \[9.8\]
Correct Answer:
B
Solution :
The system of masses is shown below. From the figure. For block A, \[F-{{T}_{1}}=\] ma ... (i) and for block B, \[{{T}_{1}}-{{T}_{2}}=\] ma ... (ii) Eq. (i) gives \[102-{{T}_{1}}\,=2\times 0.6\,\Rightarrow \,{{T}_{1}}=102-12=9N\] Again from Eq. (ii), we get \[9-{{T}_{2}}=2\times 0.6\] \[\Rightarrow \] \[{{T}_{2}}=9-1.2=7.8\,N\]