A car of mass 1200 kg tows a trailer of mass 300 kg along a straight horizontal road.
The car and the trailer are connected by a light rigid towbar which is parallel to the road.
The engine of the car produces a constant driving force of 3000 N. The resistance to the motion of the car is 600 N and the resistance to the motion of the trailer is 150 N.
Find the acceleration of the car and trailer.
Find the tension in the towbar.
State one consequence of modelling the towbar as light and rigid.
139 exam-style questions on AQA A Level Maths 3.3 R: Forces and Newton's laws, covering 3.3.1 Concept of a force and Newton's first law, 3.3.2 Newton's second law, 3.3.3 Weight and motion under gravity, 3.3.4 Newton's third law and equilibrium, 3.3.5 Addition of forces and resultants (A-level only), and 3.3.6 Friction (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.