a. Particle P moves in a straight line. Starting from rest, P moves with constant acceleration for 30 seconds after which it moves with constant velocity, k ms-1, for 90 seconds. P then moves with constant deceleration until it comes to rest; the magnitude of the deceleration is twice the magnitude of the initial acceleration.

i. Use the information to complete the velocity-time graph.

ii. Given that the particle travels 450 metres while it is accelerating, find the value of k and the acceleration of the particle.

b. A body Q moves in a straight line such that, t seconds after passing a fixed-point, its acceleration, a ms^-2, is given by a = 3t² + 6. When t = 0, the velocity of the body is 5 ms^-1. Find the velocity when t = 3.

Transcribed Image Text:

vms-t k- t seconds