14 At time \(t\) seconds a particle, \(P\), has position vector \(\mathbf { r }\) metres, with respect to a fixed origin, such that
$$\mathbf { r } = \left( t ^ { 3 } - 5 t ^ { 2 } \right) \mathbf { i } + \left( 8 t - t ^ { 2 } \right) \mathbf { j }$$
14
- Find the exact speed of \(P\) when \(t = 2\)
[0pt]
[4 marks]
14 - Bella claims that the magnitude of acceleration of \(P\) will never be zero.
Determine whether Bella's claim is correct.
Fully justify your answer.