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Question
A block of mass 2 kg is pushed against a rough vertical wall with a force of 40 N, coefficient of static friction being 0.5. Another horizontal force of 15 N, is applied on the block in a direction parallel to the wall. Will the block move? If yes, in which direction? If no, find the frictional force exerted by the wall on the block.
Solution
Net force on the block `=sqrt(20^2+15^2)-(0.5)xx40`
= 25 - 20 = 5 N
`therefore tantheta =20/15=4/3`
`=> theta=tan^(-1)(4/3)=53^circ`
Therefore, the block will move at 53° angle with the 15 N force.
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