For the truss shown in the figure, the forces F₁ and F₂ are 9 kN and 3 kN, respectively. The force (in kN) in the member QS is

A uniform slender rod (8 m length and 3 kg mass) rotates in a vertical plane about a horizontal axis 1m from its end as shown in the figure. The magnitude of the angular acceleration (in rad/s² ) of the rod at the position shown is _______

A truck accelerates up a 10° incline with a crate of 100 kg. Value of static coefficient of friction between the crate and the truck surface is 0.3. The maximum value of acceleration (in m/s² ) of the truck such that the crate does not slide down is _______

An annular disc has a mass m, inner radius R and outer radius $$2R$$. The disc rolls on a flat surface without slipping. If the velocity of the center of mass is $$v,$$ the kinetic energy of the disc is