(i)[2]
From the motion of $A$, show that the tension in the string is $3.03\,\text{N}$, correct to $3$ significant figures.
(ii)[6]
Find the coefficient of friction between $B$ and the rough face, correct to $2$ significant figures.
Mathematics 9709 · AS & A Level · Newton's laws of motion
Newton's laws of motion — practice question
The sketch depicts a vertical cross-section through a triangular prism that is secured so that two of its faces make an angle of $60^\circ$ with the horizontal. One face is smooth, while the other is rough. Particles $A$ and $B$, with masses $0.36\,\text{kg}$ and $0.24\,\text{kg}$ respectively, are joined to the ends of a light inextensible string that passes over a small smooth pulley fixed at the highest point of the cross-section. $B$ is kept at rest at a point on the rough face of the cross-section, and $A$ hangs freely in contact with the smooth face (see diagram). When $B$ is released, it moves up the face with acceleration $0.25\,\text{m s}^{-2}$.