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Question
Two blocks of equal mass m are tied to each other through a light string. One of the blocks is pulled along the line joining them with a constant force F. Find the tension in the string joining the blocks.
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Solution

Let a be the common acceleration of the blocks.
For block 1,
\[F - T = ma\]
For block 2,
T = ma ...(2)
Subtracting equation (2) from (1), we get:
\[F - 2T = 0\]
\[\Rightarrow T = \frac{F}{2}\]
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