3.1.2—F = ma and solve problems using it, understanding that acceleration and

Newton’s second law states ΣF=ma. The acceleration vector has the same direction as the resultant and magnitude proportional to it for fixed mass.

Draw a free-body diagram, resolve components and include only forces acting on the chosen body. A negative component records the chosen sign convention.

A 3 kg trolley with resultant force (6,0) N accelerates at (2,0) m s⁻².

Using one applied force instead of the resultant gives the wrong acceleration when several forces act.