Two blocks `A` and `B` are connected to each other by a string and a spring , the string passes over a frictionless pulley as shown in the figure. Block `B` slides over the horizontal top surface of a stationary block `C` and the block A slides along the vertical side of `C`, both with the same uniform speed. The coefficient of friction between the surface and blocks is `0.5 K = 2000 N//m`. If mass of `A` is `2 kg` calculate mass of `B`.
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