question_answer

Three forces \[{{F}_{1}},{{F}_{2}}\]and \[{{F}_{3}}\] are acting on a particle of mass m, such that \[{{F}_{2}}\] and \[{{F}_{3}}\] are mutually perpendicular and under their effect, the particle remains stationary. What will be the acceleration of the particle, if the force \[{{F}_{1}}\] is removed?                

Answer:

                As the particle remains stationary under the action of the three forces, so \[{{\vec{F}}_{1}}+{{\vec{F}}_{2}}+{{\vec{F}}_{3}}=0\]When force \[{{\vec{F}}_{1}}\]is removed, the net force left is \[{{\vec{F}}_{2}}+{{\vec{F}}_{3}}=-{{\vec{F}}_{1}}\]                 Acceleration, \[a=-\frac{{{{\vec{F}}}_{1}}}{m}.\]