Edexcel M3 2024 June — Question 5

Exam BoardEdexcel
ModuleM3 (Mechanics 3)
Year2024
SessionJune
TopicCentre of Mass 2

  1. A uniform right solid circular cone \(C\) has radius \(r\) and height \(4 r\).
    1. Show, using algebraic integration, that the distance of the centre of mass of \(C\) from its vertex is \(3 r\).
      [0pt] [You may assume that the volume of \(C\) is \(\frac { 4 } { 3 } \pi r ^ { 3 }\) ]
    A uniform solid \(S\), shown below in Figure 3, is formed by removing from \(C\) a uniform solid right circular cylinder of height \(r\) and radius \(\frac { 1 } { 2 } r\), where the centre of one end of the cylinder coincides with the centre of the plane face of \(C\) and the axis of the cylinder coincides with the axis of \(C\). \begin{figure}[h]
    \includegraphics[alt={},max width=\textwidth]{176ae8f8-7de9-4993-825a-6067614526ae-12_661_1194_861_440} \captionsetup{labelformat=empty} \caption{Figure 3}
    \end{figure}
  2. Show that the distance of the centre of mass of \(S\) from the vertex of \(C\) is \(\frac { 75 } { 26 } r\) A rough plane is inclined at an angle \(\alpha\) to the horizontal.
    The solid \(S\) rests in equilibrium with its plane face in contact with the inclined plane.
    Given that \(S\) is on the point of toppling,
  3. find the exact value of \(\tan \alpha\)