Q. The distance travelled by an object along a straight line in time $t$ is given by $s = 3 - 4t + 5t^{2},$ the initial velocity of the object is
A) 3 unit
B) -3 unit
C) 4 unit
D) -4 unit
Explanation
(d) $S = 3 - 4t + 5t^{2}$
$Velocity\frac{ds}{dt} = - 4 + 10\ t$
Hence, initial velocity will be
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \left| u = \frac{ds}{dt} \right|_{t = 0} = - 4\ unit$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.