Mathematics 9709 · AS & A Level · Newton's laws of motion
Newton's laws of motion — practice question
Particle $P$, with mass $0.4\text{ kg}$, is in limiting equilibrium on a plane that is inclined at $30^\circ$ to the horizontal.
(a)[3]
Show that the coefficient of friction between the particle and the plane equals $\frac{1}{3}\sqrt{3}$.
(b)[4]
A force of magnitude $7.2\text{ N}$ is now applied to $P$ directly up a line of greatest slope of the plane. Given that $P$ starts from rest, find the time that it takes for $P$ to move $1\text{ m}$ up the plane.
Worked solution & mark scheme
This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Resolve the forces to find the reaction $R=0.4g\cos30$ or $0.4g\sin30$” …