Can you solve this problem on Mechanics?

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1 Answer
Nov 13, 2016

Let the acceleration of the system be #a# and tension on the connecting string be #T#

Considering the forces on #W_B# we can write

#25xxgxxsin30-0.2xx25xxgxxcos30-T=25xxa.....(1)#

Considering the forces on #W_A# we can write

#15xxgxxsin30-0.4xx15xxgxxcos30+T=15xxa.....(2)#

Adding (2) and (1) we get

#(25+15)xxgxxsin30-(0.2xx25+0.4xx15)xxgxxcos30=(25+15)xxa#

#=>(40xxgxxsin30-(5+6)xxgxxcos30=40xxa#

#=>40xxgxxsin30-11xxgxxcos30=40xxa#

#=>a=(40xx32xx1/2-11xx32xxsqrt3/2)/40#

#=16-4.4sqrt3=8.38fts^-2#

Taking #"acceleration due to gravity"g=32fts^-2#

Inserting the value of #a# in (1)

#25xx32xxsin30-0.2xx25xx32xxcos30-T=25xx8.38#

#=>25xx32xx1/2-0.2xx25xx32xxsqrt3/2-T=25xx8 38#

#=>400-80xxsqrt3-T=209.5#

#=>261.44-T=209.5#

#=>T=261.44-209.5=51.94poundal#