The magnitude and direction of the acceleration produced in a body of mass 5 kg when two mutually perpendicular forces 8 N and 6 N act on it, are respectively:

Two blocks of masses 3 kg and 1 kg are placed in contact on a smooth horizontal surface. A horizontal force F = 5 N is applied on the 3 kg block from the left. Find the contact force exerted between the two bodies.

A ball of mass 0.5 kg is accelerated at 4 m/s2. If a second ball of mass 1 kg is to achieve the same acceleration, what force must be applied to it?