Question
Which of the following equations of kinematics are of:
(i) uniform motion
(ii) uniform accelerated motion
(iii) general motion.
(a) x = 4 - 7t2+4t3
(b) v = 4 + 5t (c) x — 5
(d) a = 9t -5 (e) a = 4.
Solution
a) x = 4 - 7t1+4t3
Differentiating 'x' twice w.r.t. time, we get
a = 24 t- 14
Since acceleration depends on time, therefore this is kinematics of general motion.
(b) v = 4 + 5t
∴ a = 5
Since acceleration of particle is constant, therefore the motion is uniform motion.
(c) x = 5
∴ v = 0
i. e. particle is at rest.
(d) a = 9t-5
Since acceleration depends on time, therefore this is kinematics of general motion.
(e) a =4
Because acceleration is constant, therefore motion is uniform accelerated motion.
