(i)[3]
Find how far the centre of mass of the object is from $AB$.
(ii)[2]
Calculate the object’s weight.
(iii)[2]
Find the smallest possible value of the coefficient of friction between the surface and the object.
Mathematics 9709 · AS & A Level · Representation of data
Representation of data — practice question
A uniform object $ABC$ is made from two rods $AB$ and $BC$ fixed rigidly together at right angles at $B$. Rod $AB$ is $0.3\,\text{m}$ long and rod $BC$ is $0.2\,\text{m}$ long. The object is in contact with a rough horizontal surface at $A$, with rod $AB$ standing vertically. It is kept in equilibrium by a horizontal force of magnitude $4\,\text{N}$ applied at $B$ and directed along $CB$ (see diagram).