Neco 2019 Physics Question 9

The velocity-time graph of a particle moving in a straight line is described as follows: (i) from \(t = 0\) s to \(t = 2\) s, the velocity increases uniformly from 0 to 4.0 m s\(^{-1}\); (ii) from \(t = 2\) s to \(t = 5\) s, the velocity remains constant at 4.0 m s\(^{-1}\); (iii) from \(t = 5\) s to \(t = 7\) s, the velocity decreases uniformly to 0 m s\(^{-1}\). (a) Determine the total displacement of the particle over the 7 s interval (in metres). (b) Find the instantaneous acceleration at \(t = 1\) s and at \(t = 6\) s (in m s\(^{-2}\)). (c) Compute the average speed over the interval (in m s\(^{-1}\)). (d) If the particle has a mass of 0.8 kg, calculate the average kinetic energy over the interval (in joules, to two decimal places).