A particle starts from rest and moves in a straight line such that its acceleration after t seconds is given by (a = (3t – 2) ms^{-2}). Find the other time when the velocity would be zero.
-
A.
(frac{1}{3} seconds) -
B.
(frac{3}{4} seconds) -
C.
(frac{4}{3} seconds) -
D.
(2 seconds)
Correct Answer: Option C
Explanation
Given (a(t) = 3t – 2), (v(t) = int (a(t)) mathrm {d} t)
= (int (3t – 2) mathrm {d} t = frac{3}{2}t^{2} – 2t)
(frac{3}{2}t^{2} – 2t = 0 implies t(frac{3}{2}t – 2) = 0)
(t = text{0 or t} = frac{3}{2}t – 2 = 0 implies t = frac{4}{3})
The time t = 0 was the starting point, The next time v = 0 m/s is at (t = frac{4}{3} seconds).