In a statically determinate plane truss, the number of joints $$(j)$$ and the number of members $$(m)$$ are related by

A two member truss ABC is shown in the figure. The force (in kN) transmitted in member AB is ________

A stone with mass of $$0.1$$kg is catapulted as shown in the figure. The total force $${F_x}$$ (in N) exerted by the rubber band as a function of distance $$x$$ (in m) is given by $${F_x} = 300{x^2}.$$ If the stone is displayed by $$0.1$$ m from the un-stretched position (x = 0) of the rubber band, the energy stored in the rubber bad is

The coefficient of restitution of a perfectly plastic impact is