In this question use g=9.8g = 9.8g=9.8 m s−2^{-2}−2.
A particle of mass 5 kg rests in equilibrium on a smooth plane inclined at an angle of 25° 25°\,25° to the horizontal. It is held in place by a force of magnitude P P\,P newtons acting up a line of greatest slope.
Find the value of PPP.
Find the magnitude of the normal reaction of the plane on the particle.
State one assumption you have made in modelling the plane as smooth.
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.