A small block of mass 5kg placed on the block of 20 kg and length is 25cm.block of mass 5 kg is placed at the right end of 20kg block.if a constant force of 15n is applied on block of 20kg horizanally the surfaces assumed 2 b frictionless.find time after whick block of mass 5kg sepreates frm 20 kg block

Dear jauneet

surface is friction less so no horizontal force will act on the 5 kg block. it will remain at rest.

acceleration of the 20 kg block = F/m  = 15/20 = 3/4

time taken by 20 kg block to travel 25 cm distance is 

 S= 1/2 at²

t= (2S/a)^1/2

  = (2*.25/3/4)^1/2

  = (2/3)^1/2  sec

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