# Revise Mechanics! (1)

A particle of mass $$m$$, initially at rest, is acted upon by a variable force $$F$$ for a small interval of time $$T$$. It then begins to move with a velocity $$u$$ after the force stops acting. $$F$$ is shown in the graph as a function of time(the curve shown is a semi-circle). Then, find the value of $$u$$.

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