Use g=9.8g = 9.8g=9.8 m s−2^{-2}−2.
Two particles PPP, of mass 6 kg, and QQQ, of mass 2 kg, are connected by a light inextensible string which passes over a smooth pulley fixed at the top of a wedge.
One face of the wedge is smooth and inclined at 30° 30°\,30° to the horizontal; the other face is rough and inclined at 45° 45°\,45° to the horizontal. P P\,P lies on the smooth face and Q Q\,Q lies on the rough face, with the string taut and parallel to a line of greatest slope of each face.
The coefficient of friction between Q Q\,Q and the rough face is 0.3.
Find the tension in the string.
Find the acceleration of the system, and state the direction in which P P\,P moves.
106 exam-style questions on WJEC A Level Maths 4.9 Forces and Newton's laws (A-level only), covering 4.9.1 Forces and Newton's laws (A-level only), 4.9.2 Forces and Newton's laws (A-level only), 4.9.3 Forces and Newton's laws (A-level only), 4.9.4 Forces and Newton's laws (A-level only), and 4.9.5 Forces and Newton's laws (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.