Edexcel M2 — Question 2

Exam BoardEdexcel
ModuleM2 (Mechanics 2)
TopicWork, energy and Power 1

2. A particle \(P\) of mass 3 kg moves such that at time \(t\) seconds its position vector, \(\mathbf { r }\) metres, relative to a fixed origin, \(O\), is given by $$\mathbf { r } = \left( t ^ { 2 } - 3 t \right) \mathbf { i } + \frac { 1 } { 6 } t ^ { 3 } \mathbf { j }$$ where \(\mathbf { i }\) and \(\mathbf { j }\) are perpendicular horizontal unit vectors.
  1. Find the velocity of \(P\) when \(t = 0\).
  2. Find the kinetic energy lost by \(P\) in the interval \(0 \leq t \leq 2\).