Que: A time variation of the position of a particle in rectilinear motion is given by x =
2t3 + t2 + 2t If v is the velocity and a is the acceleration of particle in constant units, the motion started with (Gate-2005)
(a) v = 0, a = 0
(b) v = 0, a = 2
(c) v = 2, a = 0
(d) v = 2, a = 2
Ans: (d)
Explanation:
x = 2t3 + t2 + 2t So,
Velocity v = dx/dt = 6t2 + 2t +2
Acceleration a = 12t + 2
At
the start of motion t = 0, Then
v
= 0 + 0 + 2 = 2
a
= 0 + 2 = 2
